* 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
1. There are various things tests that can just have intentions added
into them, like filters and such like, add intentions to these
2. Start thinking about being able to negate steps easily, which will
lead on to a cleanup of the steps
John Cowen