GROOVY-6990: Do not generate call site array if it's not used
GROOVY-6990: Do not generate $swapInit if not used
GROOVY-6990: Do not generate class$ method if not necessary
GROOVY-6990: Do not add timestamp fields if possible
GROOVY-6892: Oddity with Min function for Collections
make test for null comparison more generic
fix typo
Merge pull request #499 from melix/timestamp-removal

GROOVY-6990: Do not add timestamp fields if possible
Merge pull request #464 from paulk-asert/groovy6892

GROOVY-6892: Oddity with Min function for Collections