Adding a proper story feed for moving a Phriction Document

Summary: Display a proper feed title when moving Phriction Documents.

Test Plan:
{F36112, size=full}

Descriptions for the feeds you see in the image.

1. New and cool story feed
2. Fallback for the boring old ones
3. Normal story feed, unchanged

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Maniphest Tasks: T2686

Differential Revision: https://secure.phabricator.com/D5352