Don't fail lint builds for "advice"; make lint/unit upload failures louder
- When lint only has advice (no warnings/errors), consider it a "passing" build.
- Be a little louder about sendmessage calls failing because this stuff is not totally broken and that makes T8670-related things easier to catch/fix.
Test Plan: Created this revision.
Reviewed By: btrahan
Differential Revision: https://secure.phabricator.com/D13436