Rename "latex gloves" to "medical gloves"

Figured I ought to do this after I whined about it in IRC ...

Commit Message:
Minor nitpicky change - IRL, nitrile gloves are used over latex
due to latex allergens and latex's permeability to pathogens.

To avoid having to track the name change through every merge,
only the description and color are changed - "medical" gloves
so we don't have to worry about material and purple because
that's the color of the nitrile gloves I have around.