Options in the theme editors need to be translatable

Currently, enum values are used directly in the UI as names for options in the theme editor. They should be made translatable.

They should also be made human-readable, which would mostly mean adding spaces and sometimes dashes: "Background Color - Alternate" or "Alternate Background Color".

Also, tooltips are needed, because it is not really possible to know which part of the UI each selection affects, and therefore, it is easy to make a mess of the UI.

For examples of how this is done in other parts of the UI, see Options > Text Editor > Font & Colors. It would also be good to have these two editors look more consistent and function in a more consistent way.