Make document signatures visible to only document owners and signers
Summary:
Ref T3116. Currently signatures are visible to anyone, but they should be more private than that. Instead, you can see a signature if:
- It's a signature on a document you can edit; or
- it's your signature.
I'm going to lock down the signatures page a bit in general, but this makes sure that the root policy is correct.
Test Plan:
- Signed a document.
- Viewed signatures of a document.
Reviewers: chad
Reviewed By: chad
Subscribers: epriestley
Maniphest Tasks: T3116
Differential Revision: https://secure.phabricator.com/D9764