Minor: Remove commented out code
Rename: OverridingUtil#filterOverrides -> filterOutOverridden to be more precise
Add filterOutOverriding to OverridingUtil
Minor: Fix message in JetBundle
Add new functionality to "Change signature" refactoring

Extract single point of entry for all change signature refactorings and fixes (remove parameter, add parameter)
Change signature now affects overriding functions as well
Promt the user whether he wants to refactor base function(s) or the selected one if appropiate
Fix a problem with descriptorToDeclaration in JetChangeSignatureHandler
Rename: JetFunctionPlatformDescriptor -> JetMethodDescriptor
Eliminate redundant descriptorToDeclaration call from factory for "Change signature" quick fixes
Show error hint when trying to refactor synthesized function
Run "Add function parameter" fix silently if current usage is the only usage of the function
Select first new parameter in JetChangeSignatureDialog by default