Object::getStatus(), ui::Bar, TechTree stub

- matrix
  * Object::status(), getStatus() handler & Lua handler added to retrieve object
    status bar
  * Weapon/Bot/Vehicle report ammo/stamina/fuel via getStatus()
- nirvana
  * TechTree class
- ui
  * vehicle model rotates on mouse-over
  * Bar class for rendering bars
  * HudArea & Inventory show object status under health bar