Add mapgen_stair_cobble to minetest_game
Merge remote-tracking branch 'proller/sponge' into next
Merge remote-tracking branch 'proller/weather' into next
Merge remote-tracking branch 'proller/liquid63' into next
Merge remote-tracking branch 'Jordach/moonflower' into next
Merge remote-tracking branch 'khonkhortisan/diagonal_rail' into next