Adding some required fields that were not recorded

- efo_ids
- principal_investigator
Add timeseries type after discussing w/ @antgonza
BUG: Correctly set EBI status to failed

When a submission to EBI fails explicitly raise an exception so the job
status is correctly set as failed.

Additionally I removed a trailing slash from the redirect to
compute_complete/ that was showing an error on screen.

Fixes #490
Fix handling of req fields in create study command
BUG: Fix misleading comment
Merge pull request #530 from ElDeveloper/issue-490

BUG: Correctly set EBI status to failed
Merge pull request #528 from adamrp/load_study_req_fields

Add required fields for loading studies via CLI