Bot logic is now handled exclusively by the server, now in the actual game
loop code, rather than during ticcmd generation. No TICCMD_BOT needed!
botdata_t has been added to store any variables that clients don't need.
Behavior differences:
* Brakedrifting actually works now... to the detriment of the bots
* Respawn triggers 1 second sooner (and actually causes braking)
* No longer spams respawn when a track lacks waypoints
* Turning might be less responsive?
`botvars.turnconfirm += cmd.bot.turnconfirm` is gone... who knows
* No longer affected by timescale
Plus, no more outdated or copy-pasted comment blocks!