License should only appear for works with associated

[mark-dce]

STORY
As a repository owner, I do not want to allow depositors to select a license for items that are not under copyright, so that I am not providing conflicting legal context.

ACCEPTANCE

• Disable the license field if the rights statement indicates no copyright
• [BONUS] Warn the user if they try to change the rights statement to one of the no-copyright options AFTER a license has been selected.

NOTES
This probably requires some client-side JavaScript