Adapting "AbstractSniffUnitTest" to work with PHPCS 2.x

- unit test works with both 1.x and 2.x versions of PHPCS
- if "*.diff" file present then compares fixed version of file with expected one
- compares actual fixed error/warning count with expected ones
Improvements to InlineCommentSniff

- handle tabs between "//" and "comment text"
- allow any number of spaces/tabs between "//" and "comment text" (only for PHP)
- allow inline comments to also add with "," and ";" (helps with commented-out code)

Closes #33
Sniffs are now compatible with versions 1.x and 2.x