Fix #117: Implement java.lang.Character.digit
Fix #109: Handle LabelDef for while (false) {}
Fix #104: Correct hash for boxed Byte, Short and Int
Fix #116: Correct comparison for boxed Float and Double
Fix #113: Prepend a Char to String
Implement java.lang.Character.isWhitespace
Merge pull request #120 from gzm0/bugfixes

Various bugfixes
Allow to publish releases to Bintray.
Implemented System.nanoTime
Merge pull request #107 from pkolaczk/system-nano-time

Implemented System.nanoTime
Merge pull request #126 from gzm0/execution-context

Execution contexts. Enables use of Future and Promise
Remove unnecessary semicolon