codereview: match folded subject lines
codereview: match folded subject lines

Example failure from App Engine logs:

2014-06-30 08:48:46.327
('No issue id found: %s', u'Re: code review 103640044: runtime: fix GC bitmap corruption (issue\r\n 103640044 by dvyukov@google.com)')

Using \s* will match the folding as well as ordinary spaces.

LGTM=jrobbins
R=jrobbins
https://codereview.appspot.com/104430043

nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra,nicko96/Chrome-Infra