Skin Textures need compressed

[ExeVirus]

I used the mtg utils/optimize_textures on the entire downloaded character skins set, and it compressed from ~4.9 MB to ~2.3MB.

Could you please run that script (with optipng) on those textures at http://minetest.fensta.bplaced.net/? It would save minetestians some bandwidth, and yourself the hosting bandwidth. While also decreasing server load times, etc.

If we ever support webp, I might bring the issue up again then, because that'll be another 0.3-0.5 MB shaved off too.