* Add model layer support for filtering intentions by service
* Add Route, Controller and template for services.show.intentions tab
We are still loading the intentions themselves in the parent Route for
the moment
* Load the intentions in in the parent route for the moment
* Temporarily add support for returning to history -1
Once we have an intention form underneath the service/intention tab this
will no longer be needed
* Add the new tab and enable blocking queries for it
* Add some further acceptance testing around intention listings
Repositories are a class of services to help with CRUD actions, most of
the functionality is reused across various Models. This creates a new
repository service that centralizes all this reused functionality.
Inheritance via ember `Service.extend` is used as opposed to
decorating via Mixins.
1. Move all repository services (and their tests) to a
services/repository folder
2. Standardize on a singular name format 'node vs nodes'
3. Create a new 'repository' service to centralize functionality. This
should be extended by 'repository' services
