Cleaned up Code

-Fixed a bug that was causing yell's to activate units.

-Fixed the move behavior for the enemy so that they move towards the location of the shooter. Prior movement was homing in on the nearest Xcom position.

-Movement also takes much better cover now

-Added in a priority for distance as well as age of the alert in the case of Xcom having more than one sniper, so that the eneny chooses the most logical one to move toward

-Aliens pods now have 50% chance to be alerted in the event you miss your sniper shot. This can be turned off and the chance can be configured in the XcomSniperDefense.ini file.