Change Signature: Processing of non-Kotlin usages
 #KT-5810 Fixed
 #KT-4187 Fixed
Light Methods: Change PSI element language to Kotlin
Change Signature: Allow running Java's Change Signature in tests
Change Signature: Allow running Kotlin change signature from Java usage/override
Change Signature: Allow running Java change signature from Kotlin usage/override
Change Signature: Process Kotlin-based usages when changing signature of the Java function