Implement dataload_job show/edit page

[aaron-collier]

The dataload_job show page will show the status of the job, any relevant statistics, the schedule information (data load profile, processing steps) a link to download the file loaded (either manually uploaded or fetched in the pipeline).

If the job is a recurring data load, or the job has not been picked up yet, editing should be enabled so that the schedule can be update, a new file can be uploaded, etc.

[ndushay]

I'm going to create scaffolding and a rough and ready show page with mock data. This will also allow us to put links into the vendors show page to the dataload job, if desired.

[ndushay]

it should be easy to restyle as desired; I'll use the simple Gbooks approach and I won't spend a lot of time on it.