A customer on_place_node is used for seed planting. This change lets a
node with a custom right-click handler get called instead (as it would
normally) before the seed placement is done. This allows the placement
of seeds in various contains that rely on this, e.g. barrels, item
frames, without impacting on the actual use of the seeds.
Additionally, on_place_node the handler is moved to a common location
rather than being duplicated across every file.
update deprecated `minetest.env:` from Jat
Bananas and cocoa fall when tree and leaves disappear from Lukc
centralize place_seed in init from farming mod from asl97, myself
add translation support from Xanthin