Added a new endpoint /api/counters that returns %{"orgs" => x, "repos" => y} with the total amount of indexed orgs and repos (memoized at controller level, as the other endpoints).
Displaying them at home page, following the same style as org page.
Did some additional UI fixes/improves, trying to correctly display the site in all screen sizes.
This PR solves one task of #15:
/api/countersthat returns%{"orgs" => x, "repos" => y}with the total amount of indexed orgs and repos (memoized at controller level, as the other endpoints).