Search::GlobalContext and Search::ProjectContext for separation between 2 types of search

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Use new context for search

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Improve search page UX

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Better search login for global context. Improved tests

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Remove invalid test

Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>
Merge branch 'refactor/search_context' of /home/git/repositories/gitlab/gitlabhq