metatools show up in misc category

[SwissalpS]

When using unified_inventory, Huhhila reported that the tools show up in misc
category and not under tools.
I fixed postool by changing to core.register_tool(). SwissalpS/postool@91bf2d1
Have not tested if this would work as simply for metatools.

metatool/metatool/api.lua

Line 55 in 06f0bc5

minetest.register_craftitem(itemname, {

[SwissalpS]

this seems to be cleaner approach as registering as tool removes stackability.
https://github.com/SwissalpS/postool/blob/9a12983d7cf79ff0a8afdd96cdc4588f8d34e1bd/tool.lua#L40

[S-S-X]

Noticed that too when categories were added not so long ago, as other categories seemed to be bit messed up I decided to wait for some time to see if unified inventory comes up with more generic approach for this.

Probably adding that fix at some point if nothing better (something without mod dependency) comes up there.