[Input] Improved MouseState.ToString()
[X11] Removed legacy X11Input driver

Its functionality has been moved directly into X11GLNative and
X11KeyMap.
[Mac] Avoid calling into LegacyInputDriver
[Input] MouseDevice is now based on MouseState

This way we have a single state representation (MouseState), shared by
all mouse APIs and events.
[Examples] Hook both MouseDevice and Mouse events

They should give identical results.
[Platform] Remove lambdas