Adds 2 new game variations.

• "Quick Start": makes play harder, but gives players some free buffs at start.
  
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• "Arcade" mode, that doesn't stop to make buff choices- all buffs are randomly given, twice as often as usual.

In addition, it's now basically impossible to nuke your base and get blocked by your own explosions, the high-score system recognizes if you've beaten the best score in the game ever, or just beat one of the other high scores, and various other improvements!

I'll probably work on some new enemy types / variety soon. I'm really amazed that there appears to be some real interest in this game; you can help a lot if you leave a review!