Move `Mod` out of base.

[MaxMahem]

Ideally, Base should just be a struct that saves its mutable state, without any external references. Definitely not with a dependency back to mod.

Currently it's referenced in:

• Load (this will wither on the vine as things get moved out of Base into their own containers)
• Save (ditto)
• prepareSoldierStatsWithBonuses (this method needs to go)
• getUsedStores (forwards to ItemContainer, this might end up a component?)
• getDefenseProbabilityPercentage (this method needs to go)
• getShort/LongRangeDetection and detectionProabilities - needs to go, probably into a facility (also, this hardwiring is weird)
• getPersonnelMaintenance - this one is perhaps legit. Maybe ad a BaseRule for actual base related data like this.
• getUsedContainment - this method needs to go and is a mess
• damageFacilities - obviously a system

• cleanupPrisons - obviousy a system

  anyways, long term plan.