Fix course listing navbar, search.

The navbar didn't have padding. Switched it all to using bootstrap
panels, maybe it looks better, but not sure. Search was just renaming
the filtering variable to be more clear.
New breadcrumbs mechanism.

Breadcrumbs are now specified at $routes specification rather than a
value set by each controller. We're using the ng-breadcrumbs library
(https://github.com/ianwalter/ng-breadcrumbs).

When configuring routes, a "label" attribute is specified for the route,
this is used as part of the breadcrumb. The breadcrumb appears to be
formed by unravelling the url path.