Move "Introduce..." classes to separate package
Rename Jet -> Kotlin
Move Maybe class and its inheritors to util package
Pseudocode: Track PSI elements which correspond to jump instructions
Drop ReturnInstruction
Fix bug in ShortenReferences visitor (do not skip PSI elements after modication)
Extract Function: Analysis and code generation
Extract Function: UI and refactoring handler
Use lazy analysis in JetNameValidatorImpl
Auto-generate test class for "Introduce variable" refactoring
Get rid of unnecessary write action
Generalize "Introduce variable" test
Translate AbstractJetExtractionTest to Kotlin
ExtractionTest: Change test data layout
Extract Function: Add test data
Buildserver auto merge