Custom string interpolators need not be ScFunctionDefinitions.

They could just as well be function declarations, or macro
declarations.

 #SCL-5449 Fixed
Merge pull request #27 from retronym/topic/string-interpolator-prefix

Custom string interpolators need not be ScFunctionDefinitions.
plugin.xml updated.
#SCL-5191 Fixed
Do not loose that processor is Implicit after delegating it to the new processor.
SafeCheckException is ControlThrowable.
Do not take into account implicits, which are after the place and haven't explicit return type #SCL-5033 Fixed