added a new game button, and implemented methods for starting a new game
fixes in newgame implementation
small changes in newgame methods
Merge branch 'newgame' of https://github.com/Jonate/Dat255-CrayCray into newgame

Conflicts:
	CrayCray/src/se/chalmers/dat255/craycray/activity/MainActivity.java
fixed new game, and the database is now deleted and created again when new game is started
Merged in "Dev" into "newgame"
Merge remote-tracking branch 'origin/Dev' into newgame