Actively populate the sector cache on creating a Space object.
Usually happens upon entering a new system from Hyperspace, loading a saved game, starting a new game.
BIG changes due to splitting the StarSystem cache into a separate StarSystemCache class.
Tweak the sector distances used for automatic caching and StarSystemCache survival.
Remove bits of code/includes/etc that aren't necessary.
Actively populate the sector cache on creating a Space object.
Usually happens upon entering a new system from Hyperspace, loading a saved game, starting a new game.
Tweak the sector distances used for automatic caching and StarSystemCache survival.
Remove bits of code/includes/etc that aren't necessary.
Removed unused variables.
SectorCache::ClearCache to completely clear cache.
Do not assign factions to sector when called from Faction code.
Avoid instantiating Sector directly for calculating distances.
Only SectorCache and SectorCacheJob create Sector.
Merge branch 'active_sector_cache' of github.com:fluffyfreak/pioneer into active_sector_cache

Conflicts:
	src/Factions.cpp
	src/galaxy/Sector.h
	src/galaxy/SectorCache.cpp
	src/galaxy/SectorCache.h
	src/galaxy/StarSystem.cpp
bad rebase, bad merge