Workaround for buggy mouse movement in fullscreen in SDL with absolute positioning pointing devices (touchscreen, stylus). Creates an invisible hardware cursor. Borrowed from grafx2 (https://code.google.com/p/grafx2/source/detail?r=1553).
Merge pull request #794 from not-surt/master

Workaround for buggy SDL fullscreen with absolute positioning pointing devices (touchscreen, stylus)