Add support for parameter 'visual_scale' for drawtypes 'signlike' and 'torchlike' like used for drawtype 'plantlike'
Fix minetest.facedir_to_dir when param2 is 5 or 7.
Add tool callback
Fix object duplication bug (at least in the most reproducible UFO case)
Remove vector metatable setting

This not only makes the vector functions faster, but also makes them more
consistent with other functions.
Add sanity checks to vector functions
Masterserver update
Merge remote-tracking branch 'upstream/master' into masterserver