Pre-6 AI bugs

[Alejandroibo]

The new changes brought to the AI in pre6 seems to have introduced some minor but still annoying AI bugs. I'll update this issue as I keep finding them.
So far I've found:

The AI spazzes out on sentry mode:
-Pre-5: The AI will sweep one direction in a smooth manner, ocasionally turning around to watch their back.
-Pre-6: The AI will sweep once, before spazzing out and sharp aiming in random directions.
-Notes: Replacing Pre-6's HumanBehaviours.lua file with Pre-5's fixes this, so the issue must lie in said file.

The AI doesn't correctly stop when fighting.
-I can't testify wether or not this bug ocurred in earlier versions, since It very well could be some poorly desing behaviour that didn't manifest itself until the AI think times were quadrupled.
-In firefights, units set to brainhunt or go-to will sometimes continue moving foward instead of holding their ground.
-In case this isn't a bug (And honestly It probably isn't), I'd suggest adding a few seconds of wait to the AI after they lose an enemy in a battle.

[Causeless]

The AI spazzes out on sentry mode

@pawnishoovy you made some changes here as according to difficulty settings. Can you check this?

The AI doesn't correctly stop when fighting.

Yeah this isn't a bug necessarily. Basically the AI was improved to become far more responsive, and that dead time they spent "thinking" could be removed due to various optimizations. However it looks like maybe it's too responsive now and looks a little robotic, so maybe we can add a randomized idle time after it begins a new path request.