Add pipeworks compatibility to MCL chests and furnaces

[OgelGames]

There is currently only compatibility with mcl_barrels. Since we support MCL formspecs, we should add compatibility to MCL chests and furnaces.

Relevant files:
https://github.com/mt-mods/pipeworks/blob/master/compat-chests.lua
https://github.com/mt-mods/pipeworks/blob/master/compat-furnaces.lua

Related: minetest-mods/digilines#107

[SmallJoker]

Texture for overlays with mcl_chests: (inherited CC-BY-SA 4.0 as derived from pipeworks_tube_connection_wooden.png)