* ui: Add URLs to tabs to we can assert them
* Add dcs to the service show page, temporarily
There is an ongoing PR which removes the need to do this by adding a dcs
property to the navigation, hence temporary
* Add a step to assert on whether text _contains_ rather than exact match
* Test whether the URL of the instance tab changes when the user switches dcs using the main navigation menu
* Recompute href-to's on URL change, just like is-href
* Fix to bottom border not applying to the correct <li>
* Create Linked Services tab with styling and tests
* Add internal endpoint gateway-services-nodes to the codebase with tests
* Upgrade consul-api-double to version 2.15.0
* 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
John Cowen