Revert previous commit using a code change and replace it with a ruleset priority override.

It's largely unnecessary to change the PHP code for the sniffs themselves. Instead, the reported severity of any given sniff can be modified in the ruleset.xml file for the defined code standard.

This PR uses that approach to nullify detection of public methods that start with underscores (which Loadsys typically uses for `__auth()` controller methods) as well as not requiring underscores for protected methods (which doesn't always provide any additional clarity.)