List assigned issues (or, "save custom query") (BB-660)

A "assigned to me" tickets report is missing, in my opinion. In developing phases I often open a lot of tickets, and assign to me the ones I am working on. Filtering in this way will help a lot.

As an alternative (more flexible, but more complicated), the "query" menu might have a "save custom query" option, which adds the query to the list.