Directive for vertical navigation. This sets up the nav bar header with the collapse button (hamburger) and the
application brand image (or text) as well as the vertical navigation bar containing the navigation items. This
directive supports primary, secondary, and tertiary navigation with options to allow pinning of the secondary and
tertiary navigation menus as well as the option for persistent secondary menus.
The remaining parts of the navbar header can be transcluded.
Tha navigation items are marked active based on the current location and the href value for the item. If not using
href's on the items to navigate, set update-active-items-on-click to "true".
This directive works in conjunction with the main content container if the 'container-pf-nav-pf-vertical' class
selector is added to the main content container.