to comply with new plantlife API
In addition to that, there have been numerous other, smaller changes:
* Tweaked palm tree model to add coconuts
* Tweaked size of all "fruit" items (really just cones). Rotated their images
in inventory and wield.
* Changed descriptions of sideways trunks to "Sideways Xxxx Trunk"
* Tweaked names of jungle tree leaves to be Jungle Tree Leaves (Xxxx)
* Moved jungletree trunk, sideways trunk, sapling into nodedef loop
* Renamed trunks and trunk tops to bear "_trunk" and "_trunk_top" in their
filenames.
* Added copies of default jungle tree trunks and tops, with naming similar to
the above change.
* Re-arranged init.lua to put all leaves/needles definitions in one place.
* Deleted some outdated textures.
* combined leaves definitions back into main loop with an exception for
jungletrees (if that one is called for, it is skipped, because leaves for
those trees are explicitly defined later)
* Made all leaves drop saplings when dug, 1/20 chance.
* Added leafdecay radii to main tree table but disabled the use of it. To be
implemented in the future. Disabled leaf decay for firs.
