Update CHANGELOG file

Author: mikeselander

CHANGELOG.md

@@ -1,11 +1,16 @@
-## Unreleased (0.7.0)
+## Unreleased (0.8.0)
 
-### Changed
+## 0.7.0 (June 5, 2019)
+
+### Changed:
  - Exclude `load.php` from `NamespaceDirectoryNameSniff` #131
  - Allow `json_encode` / `json_decode` function usage #97
  - Fix NamespaceDirectoryNameUnitTest parsing the wrong namespace directory length #140
  - Updated location of stylelint package to reflect correct NPM name #137
 
+### Added:
+ - Made PHPCompatibilityWP available via Composer #146
+
 ## 0.6.0 (April 2, 2019)
 
 ### Summation: