Warzone - turn based strategy

- On the multi-player tab, games now sort by how long you have until you get booted. The boot time shown also takes into account banked time.
- Multi-day games now show the clock in the upper right corner just like real-time games do.
- Game creators can now invite players via distributing a 4-digit code.
- Game creators can now specify banking boot time to be added based on a schedule.
- Added new single-player levels, and tweaked some of the previously added ones.