A removed, or undefined, pure Objective-C method should raise a NoMethodError when called.

[eloy.de.enige@…]

Currently when removing a pure Objective-C method a warning is raised.

However, it would be more Ruby-ish if remove_method and undef_method would replace the methods with a stub method which raises a NoMethodError.

This way the user will still get a sensible error message when the application crashes, but will not constantly be warned when removing methods.