Previously we could not place extra nav items in a particular order.
This change introduces a new `before` attribute to addNavigationBarItem
with this attribute we can place a nav item before "top" or any other place.
Additionally this allows navigation items to force active state. In some
cases we may want an items that is simply a "filter" on latest using `?query_params`
when we do that we can "force" the filter active.
A concrete example is the assign plugin that adds a nav item for
Unassigned => `/c/cat-slug/l/latest?assigned=nobody&status=open`
If we did not force then latest would be selected even though the filter
is clicked.