Bump mypy_extensions version to 0.1.0

extensions/setup.py

diff --git a/extensions/setup.py b/extensions/setup.py
index aee20d0..b339a1e 100644
--- a/extensions/setup.py
+++ b/extensions/setup.py
@@ -4,7 +4,7 @@
 
 from distutils.core import setup
 
-version = '0.1-dev'
+version = '0.1.0'
 description = 'Experimental type system extensions for programs checked with the mypy typechecker.'
 long_description = '''
 Mypy Extensions