Added ankle holster recipe similar to holster one, fixed BELTED footwear

Added a recipe for ankle holsters with approximately half the cost of a holster or sheath, although the same difficulty. Autolearn is based upon survival rather than pistols or cutting, as it's a small utility item that can be used for either.

Changed BELTED footwear to not count as shoes, for all that entails. This means wearing an ankle holster alone does not negate the barefoot movement penalty, and you can wear an ankle holster at the same time as a pair of shoes.

This is a nice convenience now that items inside a holster are checked for butchering. Using it for a butchering tool saves you 0-3 volume and cleans up a line in the inventory screen at the cost of a little weight, which isn't an unbalanced option by the time you have both survival and tailoring at 3.