Release 1.6.0 (#70)

CHANGELOG.md

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6de1d4b..4f2809d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+# 1.6.0
+
+* Added PKCE support to `AuthorizationCodeGrant`.
+
 # 1.5.0
 
 * Added support for `clientCredentialsGrant`.

pubspec.yaml

diff --git a/pubspec.yaml b/pubspec.yaml
index 0b3d3f2..db168e3 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: oauth2
-version: 1.5.0
+version: 1.6.0
 author: Dart Team <misc@dartlang.org>
 homepage: https://github.com/dart-lang/oauth2
 description: >-