Add system indicators back to data page

Since `formatted_value` got removed from the API indicators response, system-level indicators weren't displaying on the data page.  This adds back the (unformatted) data value for system indicators, instead of displaying "No Data Available."  Also puts into translation files some untranslated strings.
If the intention was to make it a function-based field on the serializer, then yes, there's a few things wrong there.  I'll put that field as a method on the serializer on this PR then.  I thought the intention was to take it out altogether, and maybe put formatting elsewhere later.