Fixes #3125

The service isn't online, and on the long term, mmdb will likekly be
replaced with other services from the modding community.

The Irrlicht engine supports antialiasing, and Minetest already supports
saving an antialiasing setting in its configuration file.  However,
Minetest lacked UI elements to set this setting, and previously the only
way to enable the feature was by hand-editing the configuration file.

Add a drop-down menu that can enable antialiasing.

Change the name for texture pack description files from "info.txt" to "description.txt" in order to keep the naming consistent between description files for both mods and texture packs.

Also add backwards compatibility for texture packs that use "info.txt", and note in the log that "info.txt" is depreciated.

- Stop attempting to start a world when no world's created/selected in server tab
- Better world's indexes handling between subgames lists

-> remember the previously loaded serverlist, and use if new one failed
-> show a "loading" serverlist

As the fly mode option is avaiable in-game, this is not used anymore.

This fixes main menu not fitting for 800x600 (and lower resolutions) on PC builds

Create Parameters on world initialisation and set settings of old worlds

Fixes #2497.

Fixes #2037

Client now informs about incompatible servers from the list, this permits to prevent the protocol movements.
Server announces its supported protocol versions to master server

https://forum.minetest.net/viewtopic.php?f=6&t=11201
Fixed this bug.