Bank update

Changelog:

• minority politics
• pop opinions on reforms/votings
• immigration
• GDP calculations
• other countries statistics in new Diplomacy window
• new resources: Artillery, Ammunition, Firearms, Cold arms, Oil, Fuel, Rubber, Cars, Machinery, Tanks, Airplanes
• Artillery, Ammunition, Firearms, Cold arms, Cars, Tanks, Airplanes give bonus to armies. Bonus works only if all supply is present (fuel for Cars, ammunition for Artillery, etc)
• agents (population units & countries) now can properly store money in National bank or take loans. No bank interest for now (and no penalties on default)
• primitive invention AI
• bug fixing, including factory building
• attack button in province window