fix comment div alignment nits

[lonnen]

Override the negative margin on comment headers to restore padding all the way around the element. Remove width restrictions on comment inner divs that did not apply to outer divs.

Takes this:

To this:

[lonnen]

Ping?

[rik]

Sorry, I read the pull request on a phone and forgot to act on it after.

I seem to remember we don't want to change the width of fields in Bugzilla because of formatting. Checking with @globau first.

[globau]

i can't think of any reason why this would be a problem. we'll be doing a similar thing on bmo with the ui redesign work.

[rik]

Thanks for the clarification!