Cleanup - PHPDoc mismatches
Cleanup - Unused local variables
Cleanup - More PHPDoc mismatches
Cleanup - Undefined classes
Cleanup - The aftermath

Cleaning up the mess I made (and some other stuff). Also made sure
that unsetting the email pattern, respectively validating using
`filter_var()` works properly.
Merge pull request #5111 from ndm2/3.0-cleanup

3.0 - Cleanup