Prestige System

100% complete and polished prestige system. Details as follows:
 * Saves a `Math.random`ly divided portion of all your stores (barring alien alloy)
 * Only when reset at completed space sequence
 * Different divisors for Goods, Weapons, and Ammo; for balancing
 * Stores are added back into pool when visiting the Destroyed Village (U on map)

(Hopefully) precedes a scoring system I'm going to make soon.