Single/Multi Trial Upload: flexible headers & entry numbers

[dwaring87]

Description

This updates the trial upload templates to allow for flexible column headers:

• only the required columns need to be included
• optional columns can be added as needed
• columns can be in any order

It also adds support for an additional entry_number column which will assign entry numbers to accessions for the trial. (Entry numbers were previously added with PR #3770 as a separate upload).

Checklist

• [ ] Refactoring only
• [ ] Documentation only
• [ ] Fixture update only
• [ ] Bug fix
  • [ ] The relevant issue has been closed.
  • [ ] Further work is required.
• [ ] New feature
  • [ ] Relevant tests have been created and run.
  • [ ] Data was added to the fixture
    • [ ] Data was added via a patch in /t/data/fixture/patches/.
  • [ ] User-Facing Change
    • [ ] The user manual in /docs has been updated.
  • [ ] Any new Perl has been documented using perldoc.
  • [ ] Any new JavaScript has been documented using JSDoc.
  • [ ] Any new legacy JavaScript has been moved from /js to /js/source/legacy.