Misc Phame cleanup

Summary:
Ref T9360.

• View Live useless on archived blogs
• Edit Blog Image treatment like profiles
• Pager next/prev should keep you on whatever view you're on
• Unset user titles aren't falling back properly
• Add captions to edit fields for better clarification

Test Plan: Archive a blog, Edit a photo, verify pager on live and internal blogs, check empty titles, and view new edit form instructions.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T9360

Differential Revision: https://secure.phabricator.com/D16197