Use filenames with extensions

The filename "VERSION" may clash with the C++ header file "<version>"
that was added in C++20 for case insensitive filesystems.

This PR adds extensions to "src/VERSION" and "src/DESCRIPTION".

Also fast_double_parser in updated to v0.5.0.
diff --git a/.github/workflows/compile_test.yml b/.github/workflows/compile_test.yml
index 140aece..9f70b04 100644
--- a/.github/workflows/compile_test.yml
+++ b/.github/workflows/compile_test.yml
@@ -18,7 +18,7 @@
         ]
         include:
           - os: ubuntu-latest
-            python: pypy-3.6
+            python: pypy-3.7
         
     name: Python ${{ matrix.python }} on ${{ matrix.os }}
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index de77b95..70d0a16 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,12 @@
+### 1.5.2
+
+* Add file extensions to fix compilation with current Apple SDKs
+* Update fast_double_parser to v0.5.0
+* Update to Unicode 14.0.0d18
+
 ### 1.5.1
 
-* Update up Unicode 14.0.0
+* Update up Unicode 14.0.0d9
 
 ### 1.5.0
 
diff --git a/DerivedGeneralCategory.txt.sha b/DerivedGeneralCategory.txt.sha
index e72abbc..bc3753b 100644
--- a/DerivedGeneralCategory.txt.sha
+++ b/DerivedGeneralCategory.txt.sha
@@ -1 +1 @@
-068fea51fc13a8aa3154a6505d82817ed34177995fe4d881c0a253fa0aa568df7fe861487ca5b960e85cae9797b315e49a74fffe6b07e7a7ec520ac32060549c  DerivedGeneralCategory.txt
+1e82fa0f0a4cb1d230240edf97a264134681e3da9432c31abec1577744aaacd0a0609511dc12011798bad04ebb2465a30be169cb0879ab1af610533fe4ddc864  DerivedGeneralCategory.txt
diff --git a/Makefile b/Makefile
index 7d85bea..db439c7 100644
--- a/Makefile
+++ b/Makefile
@@ -8,7 +8,7 @@
 export PYTHONIOENCODING := UTF-8
 
 INCLUDES := \
-    src/VERSION src/DESCRIPTION \
+    src/VERSION.inc src/DESCRIPTION.inc \
     src/_decoder_recursive_select.hpp src/_unicode_cat_of.hpp \
     src/_escape_dct.hpp src/_stack_heap_string.hpp src/native.hpp \
     src/dragonbox.cc
@@ -16,7 +16,7 @@
 FILES := Makefile MANIFEST.in pyjson5.pyx README.rst setup.py ${INCLUDES}
 
 DerivedGeneralCategory.txt: DerivedGeneralCategory.txt.sha
-	curl -s -o $@ https://www.unicode.org/Public/14.0.0/ucd/extracted/DerivedGeneralCategory-14.0.0d9.txt
+	curl -s -o $@ https://www.unicode.org/Public/14.0.0/ucd/extracted/DerivedGeneralCategory-14.0.0d18.txt
 	python sha512sum.py -c $@.sha
 
 src/_unicode_cat_of.hpp: DerivedGeneralCategory.txt make_unicode_categories.py
diff --git a/docs/conf.py b/docs/conf.py
index 5f3a86a..05c1694 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -19,10 +19,10 @@
 master_doc = 'index'
 
 project = u'PyJSON5'
-copyright = u'2018-2020, René Kijewski'
+copyright = u'2018-2021, René Kijewski'
 author = u'René Kijewski'
 
-with open('../src/VERSION', 'rt') as f:
+with open('../src/VERSION.inc', 'rt') as f:
     version = eval(f.read().strip())
     release = version
 
diff --git a/pyjson5.pyx b/pyjson5.pyx
index 6daa79a..77e244e 100644
--- a/pyjson5.pyx
+++ b/pyjson5.pyx
@@ -1,6 +1,20 @@
 # distutils: language = c++
 # cython: embedsignature = True, language_level = 3, warn.undeclared = True, warn.unreachable = True, warn.maybe_uninitialized = True
 
+# Copyright 2018-2021 René Kijewski <rene.SURNAME@fu-berlin.de>
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 include 'src/_imports.pyx'
 include 'src/_constants.pyx'
 
diff --git a/setup.py b/setup.py
index 86d4d1e..d7d1d73 100755
--- a/setup.py
+++ b/setup.py
@@ -19,8 +19,8 @@
 
 setup(
     name=name,
-    version=get_text('VERSION'),
-    long_description=get_text('DESCRIPTION'),
+    version=get_text('VERSION.inc'),
+    long_description=get_text('DESCRIPTION.inc'),
     description='JSON5 serializer and parser for Python 3 written in Cython.',
     author='René Kijewski',
     author_email='pypi.org@k6i.de',
diff --git a/src/DESCRIPTION b/src/DESCRIPTION.inc
similarity index 100%
rename from src/DESCRIPTION
rename to src/DESCRIPTION.inc
diff --git a/src/VERSION b/src/VERSION
deleted file mode 100644
index e89f7db..0000000
--- a/src/VERSION
+++ /dev/null
@@ -1 +0,0 @@
-"1.5.1"
diff --git a/src/VERSION.inc b/src/VERSION.inc
new file mode 100644
index 0000000..e67bcd1
--- /dev/null
+++ b/src/VERSION.inc
@@ -0,0 +1 @@
+"1.5.2"
diff --git a/src/_unicode_cat_of.hpp b/src/_unicode_cat_of.hpp
index 29753bb..5a86a36 100644
--- a/src/_unicode_cat_of.hpp
+++ b/src/_unicode_cat_of.hpp
@@ -1231,7 +1231,7 @@
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
-        0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0x2au, 0x00u, 0x00u, 0x00u, 
+        0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0x02u, 0x00u, 0x00u, 0x00u, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
@@ -1869,7 +1869,7 @@
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0xffu, 0x0fu, 0xffu, 0xffu, 0xffu, 0xffu, 
-        0x0fu, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
+        0xffu, 0x3fu, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
         0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 0x00u, 
@@ -2799,7 +2799,7 @@
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
-        0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0x00u, 0x00u, 
+        0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0x02u, 0x00u, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
         0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 0xaau, 
diff --git a/src/native.hpp b/src/native.hpp
index eb9597b..4d16893 100644
--- a/src/native.hpp
+++ b/src/native.hpp
@@ -173,12 +173,12 @@
 const EscapeDct ESCAPE_DCT;
 
 const char VERSION[] =
-#   include "./VERSION"
+#   include "./VERSION.inc"
 ;
 static constexpr std::size_t VERSION_LENGTH = sizeof(VERSION) - 1;
 
 const char LONGDESCRIPTION[] =
-#   include "./DESCRIPTION"
+#   include "./DESCRIPTION.inc"
 ;
 static constexpr std::size_t LONGDESCRIPTION_LENGTH = sizeof(LONGDESCRIPTION) - 1;
 
diff --git a/third-party/fast_double_parser b/third-party/fast_double_parser
index 6a47c2a..47d76a0 160000
--- a/third-party/fast_double_parser
+++ b/third-party/fast_double_parser
@@ -1 +1 @@
-Subproject commit 6a47c2a5a1ab350f75bb167e983015d2a2be2647
+Subproject commit 47d76a06f57b19cb2e816611297071ba663b7223