Dispatcher requires controller method exist

[tysonphillips]

The Dispatcher makes a call to method_exists($ctrl, $action) to check whether the given action exists on the controller, otherwise it throws an exception. However, this does not allow for controllers to implement the magic methods __call or __callStatic to handle actions/autoloading dynamically.

Consider updating this to check whether the method_exists or is_callable.

Note: if a class implements __call then is_callable will always be true, which I think is the desired behavior, i.e., route the action to the specific controller to determine what it should do via __call.

[clphillips]

Sounds good!