R1:371051ff3779

Minor tweaks to pre/inline style for inline comments in HTML mail

Summary:
Ref T10694.

- Shift margins/padding around so inlines with multiple paragraphs get reasonable spacing.
- Add `text-decoration: none` to the "View Inline" link to kill the underline.

Test Plan: {F1265342}

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T10694

Differential Revision: https://secure.phabricator.com/D15863