Bug suggestions order

Fix bug 1030619

This PR adds:

* returns bug suggestions in a list rather than a dict, so they remain ordered to match the log file.
* returns log lines that don't match the expected ``mozharness_pattern`` like ``Return code: 1`` So they show, even though there won't be any bug suggestions for them.  For TBPL Parity
* fixed creation of bug suggestions artifacts (the two lines had been lost a few days ago)
* added a test for the bug suggestions artifacts