#74 Modal dialogs for different player hinders PBEM play

[Erik Vos]

In a game like 1830,
when the B&O private is purchased, the player must immediately set the par
value. That dialog is modal, and sometimes will interrupt someone else's
turn (depending on how the private auctions were triggered). Again, in
this case, the player cannot save the game and forward to the appropriate
party. Instead, the modal dialog must be completed before Rails will allow
the game to be saved.
(Copied from bug #2923608, as this is a different issue)

[Erik Vos]

Fixed for a few cases: 1856 repay loans and token exchange during CGR formation.
Other cases will need more time and possibly require changed to the GUI class structure.