Features:
* Cities now have 4 additional levels (5-8), allowing for roughly 3-4 times MORE building space.
* There is now a sound setting to allow muting the game's sound while in the background. Defaults to false.
Bugs:
* Fixed some z-fighting on bridges for the Linux version of the game.
* For the level 3 version of the type 1 city, the system would refuse to place city buildings built by the mayor.