major audit/cleanup/overhaul of weapon code, all identical code has been

major audit/cleanup/overhaul of weapon code, all identical code has been
merged between weapons, and the q3 weapon bob code is gone
also disabled the muzzleflash effects on the nex which were ugly, and
changed the nex effects to spawn particle effects at every impact along
the beam, which you can see after the blood clears

git-svn-id: svn://svn.icculus.org/nexuiz/trunk@1543 f962a42d-fe04-0410-a3ab-8c8b0445ebaa