Prepare 0.5.2 release

Author: squidfunk

CHANGELOG

@@ -1,17 +1,21 @@
-terraform-aws-github-ci-0.5.1 (2017-04-12)
+terraform-aws-github-ci-0.5.2 (2018-05-16)
+
+  * Fixed indeterministic environment variable mapping
+
+terraform-aws-github-ci-0.5.1 (2018-04-12)
 
   * Fixed broken update for build status badges
 
-terraform-aws-github-ci-0.5.0 (2017-04-12)
+terraform-aws-github-ci-0.5.0 (2018-04-12)
 
   * Added support to configure build specification file location
   * Fixed #10: Webhook fails due to invalid reference
 
-terraform-aws-github-ci-0.4.1 (2017-04-01)
+terraform-aws-github-ci-0.4.1 (2018-04-01)
 
   * Fixed #5: Removed default for namespace variable
 
-terraform-aws-github-ci-0.4.0 (2017-03-30)
+terraform-aws-github-ci-0.4.0 (2018-03-30)
 
   * Refactored complete code base into TypeScript