Allow -timer option in single player mode.
Add -maxgametic command line option.

Allow the game to be quit automatically / demos terminated once a
time limit is reached.
Add stuck player detection.

Detect when the bot is "stuck" (hasn't moved outside of a small area
for a certain amount of time), and quit.
Re-enable straferunning.

I previous disabled this in ea896bc... but in retrospect I don't think
this was a good idea. The bot doesn't seem to play so well with this
change applied and I don't think I really knew what I was doing.
Add -singletics command line parameter.

This allows for fast demo recording.
Add -autoquit command line option.

When this command line option is specified, quit automatically when
either 1). the level is completed successfully and the complete
intermission screen has been displayed, or 2). the player died.