WhichBot v0.4 released

WhichBot provides AI for Natural Selection, the Half-Life mod. Highlights of this release include gorge support, Linux support and improved movement code.

Detailed updates:

# Gorge support. Gorges build RTs, hives and rudimentary hive defense. They're not that smart right now - we'll work more on tuning strategy when NS 1.1 comes out. N.B. If you see one sitting still, it may be just be waiting for resources.
# Added Linux support to cater to requests from server admins.
# Updated reactive movement from happybadger. This should hopefully provide better low-level movement.
# Newly waypointed map - ns_napo. Napo is pretty well suited to bot navigation, so they seem to play fairly well on this map.
# Fixed an AI exploit where people were hiding in the hive then knifing bots that evolved. Now bots don't evolve for a while if they didn't live for very long last spawn.
# Fixed a set of crashing bugs that arose from keeping track to entities that were deleted between frames.
# Retired ns_eclipse for now, because the buggy ladders in the maintenance hive were just too big an issue with gorges playing.
# Added a bunch of tweakable parameters, including limits on the max possible number of bots and a limit to save slots for human players, as well as internal tuning parameters for build strategy, etc. More to come here. Look at whichbot.pot in the conf directory for details.
# Added a cap to the max time the pack leader waits for stragglers. Previously, the pack would get too slow when moving round the map because they were waiting for a skulk who'd died to catch up.