Integrate the damage efficiency graph in player_info.

Integrate the damage efficiency graph in player_info.

It isn't complete yet, but it is much better than before, where
new players would have a blank graph. Now it checks that the
given player has *any* accuracy or damage based weapon usage
and shows the graph accordingly. If the player does not have
five games of either, the appropriate graph doesn't show.

The incomplete part is that I'm not setting the default
weapon to show (nex and rocket launcher). If a player plays,
say, 10 games avoiding the rocket launcher then it will still
show a blank graph b/c the rocket launcher is the default dmg
weapon shown. This will be fixed, I just need to find a good way.