added rotating enemies, and enemy homing missiles

added parameters and variables to bolts. added rotating enemies as type
6, added AI for type 6 to AI switch statement. added code for drawing
rotating enemies. added a spawn code to make testing a specific enemy
type faster.
added some code for mixpanel calls. see notes.

header code in index.php, gameIndex.php, and gameOver.php.
mixpanel calls:
index.php line 46
gameIndex.php line: 47
gameOver.php line: 108
code.js lines: 430, 796, and  after each wave spawned