GROOVY-6867: Add init(), dropRight and takeRight() to List, Iterable and Object[]
GROOVY-6917: additional cleanup for @Category combined with @CompileStatic
Merge pull request #447 from yukoba/InitDropRightTakeRight

GROOVY-6867: Added init(), dropRight() and takeRight() to Iterable, List and Object[]
minor refactor: remove some unused imports and expand some * imports (expansion was just where optimize imports made such a change for files having unused imports)
GROOVY-6916: Avoid stack overflow when rendering templates and improve the syntax for in-string rendering