Create an official media kit page for Minetest

Media kit is promotional tool that contains specific information about a website, publication, games, etc. While some people thought media kits are press kits, they are slightly different in nature.

Media kit page will greatly help people who want to share about Minetest on other platforms or websites. It creates a standard guideline on how to promote the game or website.

I propose that the website to have a page of media kit, and at least includes the following:

• A simple paragraph or catchphrases that can be used to identify Minetest from all other games.
• The Minetest logo in original colours (at least in SVG, optionally PNG) -downloadable
• The Minetest logo in white-on-other-colour variant (at least in SVG, optionally PNG) - downloadable
• The mentions of the official colour codes of Minetest logo (and optionally the blueprint of the logo layout - eg the shapes and the features of the logo: I see cactus, tree, grass, sand, water, cave, is that correct?)
• A brochure and/or leaflet of Minetest (maybe ask Rubenwardy for this, iirc he has created PDF that he use to print in some conventions before? or create new one if he refuses to include his) - downloadable

Of course, all these should also be licensed the same way as the rest of the website (or mention the specific license if they were not licensed the same way).

Looking at the license file in the main repo, it looks like the base SVG file of the Minetest logo might be licensed under CC BY-SA 3.0, can someone confirm it? And the base SVG file itself is here.

I feel that media kit page should be stand-alone page but I don't mind if it's combined with the suggestions in #123