[feature request] qualifier to returns repos only.

[odoochina-dev]

sometimes when make the search, we want to first get a list of repos (of matched), then make another search in some of the repos.

Is it possible to add feature like:

1. cs.github.com/<searching_something>&some_flag
   => resp: LIST of matched repos
2. then normal cs.github.com search like currently
   further search in one or some of the repos by currently Repository qualifier