Java to Kotlin converter: fixed conversion of access to Kotlin property declared as constructor parameter
Java to Kotlin converter: minor code corrections after review
Java to Kotlin converter: checking that no element prototype assignment forgotten + no memory leaks through singleton Element instances
Java to Kotlin converter: honor external Nullable/NotNull annotations
Java to Kotlin converter: minor code refactoring
Java to Kotlin converter: specify local variable type when necessary

 #KT-5277 Fixed
Java to Kotlin converter: more correct logic for specifying field type
Java to Kotlin converter: declaring locals as var's in most of cases when needed, dropped forceLocalVariableImmutability setting
Java to Kotlin converter: fixed crash in converter + more correct auto insertion of !!

 #KT-851 Fixed
Java to Kotlin converter: added heuristics that values of types like Integer are likely nullable
Fixed KT-5315 J2K: Generate local var when parameter is being assigned

 #KT-5315 Fixed
Fixed test data
Java to Kotlin converter: keep original placement of primary constructor body + better preserving of comments for constructor
Java to Kotlin converter: do not generate redundant parenthesis for empty constructor parameters
Java to Kotlin converter: keep more than one blank line from original code
Java to Kotlin converter: refactoring working with constructors (in progress)
Java to Kotlin converter: fixed bug with secondary constructor conversion
Java to Kotlin converter: no intermediate __ variable in factory function if body is simple
Java to Kotlin converter: refactored code moving dealing with constructors from Converter to ConstructorConverter
Java to Kotlin converter: refactored code moving all knowledge about factory function internals into ConstructorConverter