Do not trigger UnusedFormalParameter with some magic methods

PHPMD incorrectly detects some parameters as unused for magic methods (ie. __call), but it is not possible to remove them from the signature since they are required by PHP.

This P/R makes the UnusedFormalParameter ignore parameters for magic methods with the following names:
- __call
- __callStatic
- __get
- __set
- __isset
- __unset
- __set_state

The functions have been filtered using two criterias, first one being that they have at least one argument, second that the signature is dictated by PHP and implementations cannot remove the parameters from the signature even when unused.