Remove counts from home navigation
Summary: Ref T12136. This just yanks the band-aid off. Fundamentally these were useful well before Dashboards and advanced bucketing, but not so much any more. They also have some performance hit.
Test Plan: Add some tasks and diffs onto a new instance, see there is no count on the home menu bar.
Reviewed By: epriestley
Maniphest Tasks: T12136
Differential Revision: https://secure.phabricator.com/D17238