Warning cleanup in the tests

Removed all unused loop variable warnings from the tests. Full build of
tests and library results in zero warnings, zero hints. There were none
in the actual FluentQuery code, however if there had been, I would
probably not have seen them due to all the test warnings.
Substring and IsomorphicTransform support
Name transform operation
Merge branch 'Substr-and-Regex-support-for-Strings'