Show packages in table of contents views in Diffusion and Differential

Summary:
Fixes T8004.

• For paths which are part of a package, show the package.
• Highlight paths which are part of a package you (the viewer) have authority over.

Test Plan:

• Viewed owned and unowned chagnes in Diffusion and Differential.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T8004

Differential Revision: https://secure.phabricator.com/D13923