Feature request: make it possible to display all instruments without a label first

On the Instrument List page, when a language is selected all the instruments are named according to their label(s) in that language. If an instrument doesn't have a label in the selected language, the place where the instrument name should be is blank. For users who want to add instrument names in a given language, it would be very useful for all the unnamed instruments to be listed first. However, I think it looks a bit bad for blank instruments to systematically appear first, because then the first thing the user sees is all the information we _don't_ have. I propose a toggle button that would say something like "Display unnamed instruments at the top" that the user can toggle if they need.

I'll put a medium priority on this just because it would be very useful for those of us who are finding new instrument names at the moment, but feel free to reduce it if I'm being too dramatic.