New modsystem
Mods are placed in $path_<user/share>/mods
They can be enabled per world in world.mt or the configure world window
Fix regression of world loading caused by 81c863ac
Remove no virtual dtor warnings, make MapgenParams contain actual NoiseParams
Install mods/mods_here.txt instead of mods/minetest/mods_here.txt
Dont load mods that have no entry in world.mt
Write mods that are not in world.mt into it at world startup
Fix EmergeThread names in log

Concatenate the thread id as string instead of adding it to the pointer
Dont teleport back if holding sneak when detaching/turn freemove off
Add a little animation when changing the wielded item
Allow nil as puncher e.g. to do damage by tnt
Fix nearly all warnings
Fix lava damage on player's upper body
Use the group "soil" for nodes that saplings grow on
Fix link in minetest.conf.example
Save settings after dropping main menu
Fix typo in particle spawning
Add menu_header.png and remove old, unused textures
Dont animate changing wielditem from hand to hand
Log non-fatal mod name conflict to actionstream instead of errorstream
Fix disappearing of wielditem