Added some experimental code for High Score
Merge branch 'master' of https://github.com/ayrten-cofounder/Ayrten-Scrots

Conflicts:
	core/src/com/ayrten/scrots/game/ChallengeGameMode.java
	core/src/com/ayrten/scrots/highscore/HighScore.java
	desktop/src/com/ayrten/scrots/desktop/DesktopLauncher.java