Enabled status and selector (and tags?) should not be cleared on re-imports

I haven't done a lot of re-importing myself, so hadn't run into this, but apparently some users have found it very annoying to have to re-enable fonts after imports. It should retain both enabled and any CSS selector. I'm not sure whether it makes more sense to retain tags or reset them on import. This will need to be done separately for each provider, since import works a bit differently for each.