Consistently give responsibility for thread sleeping to behaviours rather than controlling from the main action loop

This is to avoid excessive and inconsistent delays between behaviours that currently need to embed sleeps in other actions (e.g. physics) and other behaviours.
Might need a more sophisticated approach in the long term.
Make pCampbot "add behaviour" and "remove behaviour" console commands work for all bots if no bot number is given
In pCampbot PhysicsBehaviour.Close(), only cancel jumping if bot is connected