Fixed issue with mouse jumping occasionally from setMouseExclusive

There was an issue that I noticed when calling setKeyboardEnabled() for the FirstPersonInputHandler. If I had the mouse movement disabled when I would suspend and unsuspend the keyboard the mouse would jump to a different location. What was happening was that suspending and unsuspending the keyboard was triggering setMouseExclusive() in InputManagerImpl. When this happens regardless of whether or not the MouseDevice's exclusive property is already set to what it is trying to set it to (Ex: Setting the MouseDevice as not exclusive even when it wasn't exclusive) setExclusive() was being called on the AWTMouse. When this happens and the MouseDevice is being set to be not exclusive and it is already set as not exclusive, the AWTMouse from HIAL would think that the mouse was just losing exclusiveness so it would set the mouse position to the last known coordinates. These coordinates are outdated and would cause the mouse to jump to another location.