Disable the edit/quote menu for non-standard comments

Summary: Fixes T4930. We currently show the edit/quote menu if a transaction group has //inline// comments, but this doesn't make sense and doesn't work properly. Only show this menu if the group has a normal comment.

Test Plan:
Viewed these groups:

  - Normal comment (edits fine).
  - Just inlines (no more edit menu).
  - Inline + comment (edits fine, affects the normal comment properly).

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: bitglue, epriestley

Maniphest Tasks: T4930

Differential Revision: https://secure.phabricator.com/D9180