Drone Tweaks, Adjustments, Additions

Some tweaks and additions to drones

**Commit log:**

1e51b88
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* Drones can hear and understand human speech, but still cannot speak it
* Drones recieve 25 brute damage when hit by a heavy EMP blast
* You can tell if drones do not have a player controlling them
* If you attempt to repair a dead drone, but the player is ghosted and can re-enter, you will repair it, and the ghost will be notified
* Added new get_ghost proc to mobs, which will attempt to retrieve the ghost mob of the player if it exists and can re-enter, override arg available if you want it even if it can't re-enter
* Syndrones now start with initial TC/2 instead of a hard coded 5 (which was made before the TC*2 update)
* Drones get a robotic chat bubble
* *Allowed drones to be weakened, as an addition to already being stunned (Forgot to add to commit log)*
* *All ghosts now hear drone chat (Forgot to add to commit log)*