Separate editing of package data and paths in Owners

Summary:
Ref T8320. There's currently one enormous form; split it into a general information form (name, description, owners) and a paths form.

I think this is a little more manageable from both a UX point of view and from an "I have to convert this to use ApplicationTransactions" point of view.

Test Plan:

• Edited paths.
• Edited non-path information.
• Created new packages.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley

Maniphest Tasks: T8320

Differential Revision: https://secure.phabricator.com/D13026