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[avdata99]

After #30 and #31

If a regular editor user defines IATI fields, it will fail after the resource save in the iati actions so we should only display IATI fields (defined at #30) if the user is a organization admin

Also, we need to ensure we don't loose this IATI fields values when a regular user (no org admin) saves a IATI resource.
So a specific test case is requiered:

• A org admin creates a IATI file (filling the IATI fields)
• Then a regular editor updates the resource name
• Ensure the internal resource IATI extra fields remains with original values

[avdata99]

Closing #49
pause this issue, we need to re-think it later