drawing an animated line to the attacked field
The line is in AimSelectionScreen drawn.
Merge remote-tracking branch 'origin/master'

Conflicts:
	src/animation/AnimatedLine.java
rotating arrows
First of all, I merged AnimatedLine. After that, I fixed some bugs and then I tried to rotate the images of the arrows, however it does not work correctly. They rotation is slightly to low/high or even doesn't work, but the idea is already implemented.