cic: about to test phase4
Add phase5, all passes
Remove ctx from Player
Fix bugs in buying cities
Money checker
Money checks
minor simple-round test updates
Rename PowerCitiesMessage's field for clarity
Store turn-order in game, phase5 fixes

Simplify things a bit and directly store the current round's turn order on the
game object. Using the sorted-map would cause turn-order to update mid-round
(after power-plants/cities purchased).

Also includes various phase5 fixes, modifications. Adds more specific validation
error messages