Merge remote-tracking branch 'origin/upstream'

data/junglegrass.png

data/jungletree.png

data/jungletree_top.png

po/en/minetest.pot

src/collision.cpp

src/content_craft.cpp

src/content_inventory.cpp

src/content_inventory.h

src/content_mapblock.cpp

src/content_mapnode.cpp

src/content_mapnode.h

src/defaultsettings.cpp

src/environment.cpp

src/game.cpp

src/inventory.cpp

src/inventory.h

src/main.cpp

src/map.cpp

src/mapblock.cpp

src/mapblock.h