Fix Oblivious skin summary remarkup and partially fix title

Summary: Ref T9546. I only got the title to always show the blog title (better than nothing) -- showing the post title properly isn't trivial and is more work than I want to do right now.

Test Plan:

• Description now has remarkup.
• Title now shows blog title (better than nothing).

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T9546

Differential Revision: https://secure.phabricator.com/D14423