Add more transation data to panel tab changes

Summary: Fixes T10473. Clever, didn't know we could do this, but works well. Renders out the tab names by ', '.

Test Plan:
Add a tab panel, change some names, review transactions.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Maniphest Tasks: T10473

Differential Revision: https://secure.phabricator.com/D17359