Feature request description

I would like to have the site search facility of Sourcegraph be extended so that lang: Mojo works.

Is your feature request related to a problem? If so, please describe.

It's difficult to narrow searches down by other means, especially since the term mojo crops up in other contexts, eg. Mojolicious.

Additional context

Github themselves have, in the last few days, started to recognise Mojo as a distinct language, so there's no excuse now 😉