Merge pull request #213 from jwagenleitner/GROOVY-5898-fix

GROOVY-5898: fix for empty quotes
GROOVY-6217: The Edit command should replace the shell buffer, not append.
minimal refactoring after GROOVY-6217: updated copyright, use power asserts
remove unused files
GROOVY-5436: fix test
GROOVY-5436: move testCastingNotConfusedWithNamedParameters_5111 test so tests do not rely on access to Sql#preCheckForNamedParams
GROOVY-5436: refactoring ExtractIndexAndSql
GROOVY-5436: added placeholder expansion for Collection/Array parameter types