Filter by project in group/dashboard issues lists

Filter by project in group and dashboard issues lists.

Depending on further implementation/investigation, we may want to do this together (or separately in another MR), the same thing for merge requests.

### Problem

There's author, assignee, milestone and label filter, but no project filter

Add an additional dropdown filter that allows you to filter by project.

Edited Jan 07, 2019 by Victor Wu