Extract routes spec into their own spec file
Spec route_collection_path with belongs_to
route_collection_path and route_instance_path both return the path as a String

Conflicts:

	lib/active_admin/comments.rb
Spec route_instance_path
Add support for belongs to to route_instance_path
Delegate route_*_path to a RouteBuilder
Refactor RouteBuilder
Fix auto_link helper after method signature change
Move route_uncountable? back to the Resource class as it's overwritten
by PageResources
Merge pull request #2099 from gregbell/fix-instance-route

Fix `route_instance_path`