Medieval Overhaul Deep Vein Mining

This is purely a patch with no included assets. Converts the vanilla deep drill into a deep vein mineshaft, and ground penetrating scanners into prospecting desks. Both are medieval technologies. They are otherwise identical to their vanilla counterparts.

Both buildings still need 1 power, which is provided by the "mining bird", which is different from the messenger bird. Medieval Overhaul updated their messenger birds in 1.5 to have a more elegant connection to the scribe table, but trying to use these with the prospecting desk breaks functionality. As it is only a reskinned Ground Penetrating Scanner, and the GPS needs to be powered so you can see the discovered deposits, removing power consumption renders all your discovered ore deposits invisible. So I re-added the old 1W birds with a new name. On the plus side, you are no longer using highly trained messengers as gas detectors.

Requires Medieval Overhaul.

Also removes gold, silver, plasteel and steel as possible results from the prospecting table/subsurface scanner. Since iron, gold, plasteel and silver ores exist in Medieval Overhaul, you'll find those instead.

Soft incompatibility with Vanilla Textures Expanded - Variations, as it overrides the ground penetrating scanner graphics so you'll get a subsurface scanner again instead of the prospecting table.

This patch points to the Medieval Overhaul textures for the mineshaft and scribe table, so you'll find those doubled up in your build menus.

Thanks to the Medieval Overhaul team.