Make Read*Node functions take the entire node block
Fix bots twitching when roaming.

BotFindRandomPoint gives a random point on the navigation mesh, but the navigation mesh height may be significantly different from the floor's height. This could result in a goal that is always > 70 units from the bot no matter how close they get.
Don't check for target movement when the target does not move

This is a better solution for some excessive route replans.