Merge pull request #5 from JavaSaBr/master

fix NPE during clear scene
test implementation of dragoffset

Signed-off-by: Kai Börnert <kai-boernert@visiongamestudios.de>
added getter for innerscroll of windows

Signed-off-by: Kai Börnert <kai-boernert@visiongamestudios.de>
Merge remote-tracking branch 'master/master'
Changing the implementation of determining the amount of decoration
windows