Users and projects may now be selected using typeahead search

This patch depends on user and project LIKE filtering on the API. It
enables usage of those filters to provide a typeahead-style search to
assign the values of both a task's assignee and its project.

Also removed zombie template in detail view.

Change-Id: I35da590c04024105893ef77e71d471a9c022e88d
Merge "Users and projects may now be selected using typeahead search"