Improve search results page

After searching for a keyword the first message that i see is
We couldn't find any results matching itau which is not true, it could not find projects with that name or description but it found two issues and three merge requests if you take a look at the navigation tabs at the top.

This is most of the times confusing i think we should show all results in one page separated by categories or
only show tabs where we had results(which can still be confusing).

Proposal

While we are waiting for https://gitlab.com/gitlab-org/gitlab-ee/issues/11777, we are first going with updating the copy from 'results' to e.g. 'projects'. This should solve the context issue while we are waiting for the speed improvements to arrive.