Move games/minetest to games/minimal and update README.txt

games/minimal/mods/default/textures/default_torch.png

...inimal/mods/default/textures/default_torch_on_ceiling.png

.../minimal/mods/default/textures/default_torch_on_floor.png

games/minimal/mods/default/textures/default_tree.png

games/minimal/mods/default/textures/default_tree_top.png

games/minimal/mods/default/textures/default_water.png

games/minimal/mods/default/textures/default_wood.png

games/minimal/mods/default/textures/heart.png

games/minimal/mods/default/textures/player.png

games/minimal/mods/default/textures/player_back.png

games/minimal/mods/default/textures/treeprop.png

games/minimal/mods/default/textures/wieldhand.png

games/minimal/mods/experimental/depends.txt

games/minimal/mods/experimental/init.lua

...mal/mods/experimental/textures/experimental_dummyball.png

games/minimal/mods/give_initial_stuff/depends.txt

games/minimal/mods/give_initial_stuff/init.lua

games/minimal/mods/legacy/depends.txt

games/minimal/mods/legacy/init.lua

games/minimal/mods/legacy/textures/apple_iron.png