graph: reworked buckets so they can handle very large number of nodes
aim: bots should more respect headshot allow option (needs testing)
aim: incorporated never-finished changes from pr #204
nav: increased reachability timers a bit
nav: ensure buckets has enough nodes before use they
conf: introduced max recoil in difficulty config file
bot: overall fixes to jason mode, treat knife in hands and no weapons as jason mode too
bot: changed default difficulty level for bots to level 3
fix: knife attacks not working since last commit (fixes#429)
fix: hostage rescue not working since last commit (fixes#427)
refactor: use range loops for graph outside graph class when possible
