Gamesetup Map Browser

[elexis]

• Currently only the host can see the map.
• In order to see the map preview image of a map, one has to change the map using a dropdown object. Many users don't know that the arrow-keys allow browsing through the maps.

In order to chose the most interesting map in the gamesetup screen, every player participating in the match including the host should be able to view all maps on a separate screen, allowing them to visually compare them without user interaction.

• MapFilters would allow to only see land, naval or trigger maps.
• Clicking on a map should select it
• Map Description should be displayed, at least in the tooltip
• The right side could show a panel with a magnified selected map preview + map description label, similar to the lobby/gamesetup/savegame screen.
• Since scrolling isn't available, paging needs to be used.

Discussed with nani in the lobby and a started implementation by nani in ​https://code.wildfiregames.com/P135

[Imarok]

Move tickets to Game Setup as UI & Simulation got some sub components.

[wraitii]

In 24459:

Map browser, used in the gamesetup and in the main menu.

This grid-based system allows browsing all available maps at a glance, encouraging more diversity and making it nicer to pick a map.

Moves the mapCache and the map filters controller to the gui maps/ folders, and include that folder where it is used, instead of them being in common/ or the gamesetup.

Comments By: Freagarach

Patch By: Nani (reworked by elexis then wraitii)

Fixes #5315 (though further work, such as proper scrolling, would be nice).

Differential Revision: ​https://code.wildfiregames.com/D1703