* Squash project users selectbox and users selectbox into one class
* Move from API autocomplete to GitLab internal one
* Smarter filter for project/group/all issues
* Use selectbox with searchbox for assignee/author/milestone/label
* Switch to ajax filter for issue author/assignee

* disable sticky headers in discussion
* enable sticky header on mr page with you click changes tab

Closes #1274

* count opening of issues and merge requests
* dont trigger git repository - use events from database
* much-much faster since does not affected by repository size

It is same search like we have at issues page. It allows to quickly
filter merge requests based on title or desription. I copy-pasted some
js code from Issues.js. In future search (filtering) logic should be
refactoed into one class for merge requests and issues

* Add search filtering for group projects
* Show all user projects on dashboard
* Refactor projects list into one view
* Hide big list of projects with 'Show all' button