Add Victoria 2 Compatibility

[Valerus9]

Implement everything needed for a complete recreation of the original game.

NOTE: Currently it doesn't check off anything that is already done.

UI

• Add Loading Screens #457
• Add Main Menu #458
• Add Tutorial #459
• Add Credit Screen #460
• Add Options Menu #461
• Add Lobby Screen #462
• Add Country Interface #463
• Add Map UI #469
• Add Production Screen #471
• Add Budget Screen #480
• Technology screen
• Politics screen
• Population screen
• Trade screen
• Diplomacy screen
• Military screen
• Province menu
• Selected army/navy menu
• Battle plan editor
• Messages filter settings
• National focus selection menu
• Pop detail menu
• Esc menu
• Ledger
• Find Country or Province
• Messages chat (the one which writes out military alliences, etc.)
• Resign/end of game "result" screen
• Multiplayer loading menu
• Player chat ("Tab" chat)
• Outliner (list of armies, navies, influence, constructions, etc.)
• Casus Beli selection menu (Justify war goal, Add Wargoal, Declare war, Offer peace)

Mechanics

• Loading screens
• Link buttons
• Multiplayer menu
• "tab" chat
• Option's Game, Video, Audio, Controls submenu
• Tutorial's Basic, Medium, Advanced submenu
• Country select player chat
• Country select screen
• messages chat
• Outliner
• Batte plan editor
• esc menu
• Ledger
• find province or country
• Production screen
• Budget screen
• Technology screen
• Politics screen
• Population screen
• Trade screen
• Diplomacy screen
• Military screen
• World map screen
• Music
• Unit controls (Land/navy unit movement, etc.)
• Daily tick calculations
• Client Host Communication
• Log file creation
• Catch file creation
• Save files
• AI
• Mods
• Checksum

Graphics

• Add Map Graphics #470

Launcher

• Create custom OpenVic launcher