Added Input class and derivatives to represent key and mouse button presses.
Added virtual destructors to the display server subclasses.
Added PressState to Input.
Added Input_Event.
Made BindingCondition test against an event.  Added Input_BindingCondition to test against an input event.
Lots of changes:
- Got rid of WindowDataMap class and typedef'd it as a standard map.
- Added GetWindowByWindowID method.
- Do some cleanup in the destructor of X11XCB_DisplayServer.
- Added InitializeClientWindow method.
Added *_NOHEADER log macros.
Added a little reminder to Vector.