restangular is an AngularJS HTTP utility library meant to wrap $http calls and provide a RESTful abstraction. You are supposed to query a resource, for example a milestone, get back an object and use that object in your data model. Later, you can call directly sub-resources from the "restangular-wrapped object".
But (fortunately) our usage is different: we use it as we would use $http: we do some requests and just return the result, without ever calling methods on the resulting wrapped objects.
It is fortunate because it means our usage is not deeply tied to this particular library. As we are looking to get out of the AngularJS world, we should start by migrating AngularJS services away. We'll start by getting rid of restangular in favor of our TLP fetch wrapper.
As restangular is used throughout our AngularJS apps, several requests will be needed to get rid of it completely. We'll start with planning view.