debugging

- support for custom prefab sell lists in the faction definitions
- command to generate prefabs for sale on already generated stations (without the need to regenerate whole economy) /npc economy sellprefabs, this commands can be used to shuffle what ships stations are selling as well, to spice things up
- /npc economy generate & /npc economy station commands will already generate stations with prefabs to sell (base set is coprised out of the ships sold by vanilla economy)

configurable despawning and cleanups

space rescue mission (ship, pod, black box) difficulty is now taken into account (the grid to be rescued moves based on the difficulty)

/npc mission show command, shows information about the active mission

when checking npc faction relations, don't check against themselves

/npc help command updated

players have access to /npc info <faction tag> version of the /npc info command, this can tell them the relations of specific faction to other NPC factions, including the player factions.

audio fixes