Game crashes

[PavanLuca]

Probably an excess of mobs, in fact there were many around while some alien ships were still dropping more when this happened for the first time. Anyway happened on any new world that I created.

	AsyncErr: Lua: Runtime error from mod 'torrl_aliens' in callback luaentity_Step(): ...etest/games/torrlund/mods/ext_libs/creatura/mob_meta.lua:1009: attempt to index local 'vel' (a nil value)
stack traceback:
	...etest/games/torrlund/mods/ext_libs/creatura/mob_meta.lua:1009: in function '_physics'
	...etest/games/torrlund/mods/ext_libs/creatura/mob_meta.lua:857: in function <...etest/games/torrlund/mods/ext_libs/creatura/mob_meta.lua:830>