Ebi submit page

_Mostly_ there. This is not linked up yet, so you have to go to the page manually (e.g., `localhost:8888/ebi_submission/1`. Second, `send` is forced to `False` right now so it is not sending. The actual submission is done on a worker, and allows for a somewhat general way to submit arbitrary compute with a waiting page.

It is awkward to push and publish messages, and I think there is a better way, but this works as far as I can tell.
@josenavas @adamrp, can you take a look at this change specifically? The `to_file` methods were not returning prep and sample templates as structured on load, which broke the EBI submission code as it expects `sample_name`.