Redo how we ingest content to work in an asynchronous way

[TheNewAutonomy]

Importing a video can be time consuming so what we should be doing is validating the video upload form, creating the empty asset then completing the ingest, transform and publish actions in the background.

In principle this is straight forward, we just asynchronously call a method to carry out those actions.
However, we need to thing about this a little further since we want to provide the user with either a visual aid of the progress happening in the background or a page to go and view background upload processes.

So there's a design and development piece that needs to be carried out for this.