Rename __callstatic (internal name) to __callStatic (userland name)

[d3y4n]

In error messages.

class StaticFtw {
    public function __callStatic(){}
}

StaticFtw::foo();

PHP gives following error message:

Warning: The magic method __callStatic() must have public visibility and be static
Fatal error: Method StaticFtw::__callstatic() must take exactly 2 arguments

(Note the second error message).