Fix possible crash with grass ABM.
Implemented facedir in the nyan cat rainbow
Revert dig time in creative mode to 0.5

This made it impossible to punch things without breaking them in creative
Fix tree growing and jungle sapling growth rate
Add 6d facedir to logs.
Allow cactus to lay on its side also.
Rewrite player.lua
Fix indentation, use log() instead of print() and use get_item_group() in tree growing ABM
Remove / replace all print() calls
Add is_ground_content setting to grass_1, apple, and dry shrubs
Explicitly set values of is_ground_content

Counterpart commit to minetest 9a927476
Add waving property for leaves and plants.
Fix player skin changing code.
Use minetest.swap_node instead of hacky_swap_node
Rework screwdriver and add protection support
Check for area protection in buckets
Shorten lines in bucket and support nil placers
Allow changing screwdriver mode when pointing at a protected node
Add protection support to signs
Prevent bucket from replacing unloaded nodes