add child and children route dsl functions

[foxnewsnetwork]

Right now, I use model#collection, but that really should be split into child and children in the router dsl to better allow auto-route to determine how to handle defaults

[foxnewsnetwork]

in this same vein, roll DSL data into a service that way, their handling gets correctly managed by ember

[foxnewsnetwork]

done. Use in the router.js file like so:

Router.map ->
  {namespace, model,  collection, form, view, child, children} = DSL.import @
  model "appointment", ->
    children "import-batches", as: "batch", -> form "new"
    children "export-batches", as: "batch"