Add .kotlin to gitignore (#1333)

Add .kotlin to gitignore as these are build files and should not be commited

Author: Stefterv

.gitignore

@@ -93,6 +93,7 @@ gradle-app.setting
 # Java heap dump
 
 # End of https://www.toptal.com/developers/gitignore/api/android,gradle,java
+.kotlin/
 .DS_Store
 bin/*
 .build/