Release report tweaks

[daveoconnor]

1. "Do it all", rename -> "Get Release Report Data".
2. Rename release report button to "Create Release Report", move to release reports part of admin interface.
3. Add locking to release reports to prevent publishing over locked published ones.
4. Block creation of older release reports
5. Admin UI: Only delete the published pdf file when the most recent published release report row is being deleted, check for newer release report records with the same filename when deleting older published release report records. Older published release report records can be deleted without the file being deleted.
6. "Get Release Report Data" (formerly "do it all") will no longer generate a release report.