Hide uncraftable items

[SmallJoker]

This setting only applies to non-creative players.

Requested by @nininik0 in https://forum.minetest.net/viewtopic.php?p=432038#p432038

How to test:

1. Check whether the inventory still shows the items as they are used to be.
2. Set unified_inventory_hide_uncraftable_items = true
3. Make sure that the world does not have creative mode enabled and that you do not have the creative privilege.
4. Notice the lower page count in the "all" category

[Niklp09]

Seems to work. But I would like to have an option, to only hide items which aren't used in any recipes too.

[nininik0]

Dosent work, I pasted it into the init.lua and minetest.conf, still shows admin items that are uncraftable, creative mode is off and i did /revokeme all and /revokeme creative,

There's also another issue with 3d_armor inventory thing