Disabled the following (for MSVC only) that couldn't (or shouldn't) be fixed.
4003: not enough actual parameters for macro 'identifier'
4250: 'class1' : inherits 'class2::member' via dominance
4251: 'type' : class 'type1' needs to have dll-interface to be used by clients of class 'type2'
4275: non dll-interface class 'type1' used as base for dll-interface class 'type2'
We need to make sure it's not stay active during gameplay.
Proper fix would require actually removing menu interface from GH, but then GH needs refactoring too.
New features for players:
* Loading for multiplayer. Any save could be used for multiplayer.
* Restart for multiplayer. All clients will restart together.
* Loading from single save.
* Hotseat mixed with network game. Multiple players per client.
* Now connection to server could be cancelled.
* Return to menu on disconnections instead of crashes.
* Restoring of last selected map, save or campaign on next run.
TLDR on important changes in engine code:
* UI: work with server separated from UI
* UI: all explitic blitting replaced with IntObject's
* UI: all new code use smart pointers instead of DISPOSE
* Gameplay always start through lobby controlled by server.
* Threads receiving netpacks now shared for lobby and gameplay.
* Campaigns: heroes for crossover now serialized as JsonNode.
