Navigation Overhaul

Built in support for the concept of "NavigationRouteOptions" to clean up
the code smell of "ShouldBreakAfter". Refactored the navigation list
builder to support groups. Added support for "pull-right" on menu group
ULs. Moved area information into the NavigationRouteOptions class.
Updated and added tests as necessary. Updated samples, added comments
and example route filter to sample project.