Added ability to get the current GameParams.

Fixed fullscreen/windowed mode support.
Fixed cursor visibility. Default to be visible is not given in fullscreen. Now always set correctly.
Added variables for window title and mode. Also added variable for cursor visibility. Added them so one can ask for their values with getCurrentGameParams.
Added Show instance for GameParam.
Merge pull request #2 from jbracker/master

Added getCurrentGameParams and fixed a few minor bugs.