Add a "members of all projects" (vs "...any project") custom policy rule to the upstream

Summary:
Ref T13151. See PHI702. An install is interested in a "members of all projects" (vs "members of any project", which is currently implemented) rule.

Although this is fairly niche, I think it's reasonable and doesn't have much of a maintenance cost.

This could already be implemented as an extension, but it would have to copy/paste a bunch of code.

Test Plan:

• Ran unit tests.
• Used the UI to select this policy for a task, with various values. Joined/left projects to satisfy/fail the rule. Behavior seemed correct.
• Used the UI to select the existing policy rule ("any project"), joined/left projects to satisfy/fail the rule. Doesn't look like I broke anything.

Reviewers: amckinley

Reviewed By: amckinley

Maniphest Tasks: T13151

Differential Revision: https://secure.phabricator.com/D19486