Slide Changes/fixes
Preloader changes
Build City -> reconfigured
Added changed() for new Army and City
City.as
  - fixed buildingQueue()
  - fixed advanceBuildings()
Battle Changes
  - added retreat
    -- ability to choose to retreat after loss of 50%
    -- random retreat -> Army
  - added alert
    -- start/cancel battle
    -- retreat/rally
    -- ok (continue)