prepare v0.6.20 (#1163)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b0e15b..6d2586a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,9 @@
+# 0.6.20 (November 21, 2019)
+
+### Fixed
+- Use default IOCP concurrency value (#1161).
+- setting FD_CLOEXEC in pipe (#1095).
+
 # 0.6.19 (May 28, 2018)
 
 ### Fixed
diff --git a/Cargo.toml b/Cargo.toml
index b4480d6..020ce2c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,11 +6,11 @@
 # - Update CHANGELOG.md.
 # - Update doc URL.
 # - Create git tag
-version       = "0.6.19"
+version       = "0.6.20"
 license       = "MIT"
 authors       = ["Carl Lerche <me@carllerche.com>"]
 description   = "Lightweight non-blocking IO"
-documentation = "https://docs.rs/mio/0.6.19/mio/"
+documentation = "https://docs.rs/mio/0.6.20/mio/"
 homepage      = "https://github.com/carllerche/mio"
 repository    = "https://github.com/carllerche/mio"
 readme        = "README.md"
diff --git a/src/lib.rs b/src/lib.rs
index 629147e..2369e4c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,4 +1,4 @@
-#![doc(html_root_url = "https://docs.rs/mio/0.6.19")]
+#![doc(html_root_url = "https://docs.rs/mio/0.6.20")]
 // Mio targets old versions of the Rust compiler. In order to do this, uses
 // deprecated APIs.
 #![allow(bare_trait_objects, deprecated, unknown_lints)]