Killfeed icon, Updates to abilities & CFG

Killfeed icon for rockets now registers as a meteor shower spell
kilfeed.

rage_blitzkrieg now blitzkrieg_barrage

rage_miniblitzkrieg now mini_blitzkrieg

ammo config for rage/death effect part of blitzkrieg_config. Hopefully
to add cvar to allow temp/permanent editing on-the-fly without needing
to restart server

gravity can now be adjusted to your liking!

Still experimenting with the reanimator entity & the weapon override
stuff.