Java to Kotlin converter: code refactorings after review
Java to Kotlin converter: added tests for 2 old issues
Java to Kotlin converter: "//file" in test data has made optional
Added test for KT-3367
J2K: supported synchronized, volatile, transient and strictfp

 #KT-3678 Fixed
Fixed KT-5276 J2K: Convert calls to getClass() to javaClass property access

 #KT-5276 Fixed
Fixed KT-5383 J2K: preserve annotations from primary constructor + never drop constructors with annotations

 #KT-5383 Fixed
J2K: correct conversion of nested class references

 #KT-5294 Fixed
 #KT-5400 Fixed
J2K: got rid from Converter.convertElement + fixed local classes conversion

 #KT-5202 Fixed
J2K: moved part of code into special AnnotationConverter to make Converter.kt smaller
J2K: more correct set of annotations to drop
J2K: Fixed conversion of <primitive type>.class

 #KT-5428 Fixed
J2K: adding type arguments where they are needed and removing them where they are redundant
Fixed KT-5443 J2K converter crashes when code contains catch with multiple exception types

 #KT-5443 Fixed
Fixed assertion + refactored code making it more simple
J2K: fixed bug
Fixed KT-5247 Java to Kotlin: convert java @interfaces into Kotlin annotation classes

 #KT-5247 Fixed