Target selection

Added a new key (default: "M") for selecting a target between multiple opponents. Note that it also aligns the camera to be behind the player when nothing is targetted. No mouse movement is used during the demo.

Not shown in the video is the new engine feature to allow for implementation of additional key inputs while still retaining the control setup across different patches.

Looking back at this particular video it almost looks like a turn based game. Hmm...