Implement viewer() and members(project) typeahead functions
Summary:
Ref T4100. This is still a bit rough around the edges, but mostly does what we're after.
- Implements viewer() and members(...) functions.
- The new browse workflow makes these discoverable.
Test Plan:
Reviewers: btrahan
Reviewed By: btrahan
Subscribers: chad, epriestley
Maniphest Tasks: T4100
Differential Revision: https://secure.phabricator.com/D12444