bug 1445641: Ignore SpeedCurve in-progress 403
bug 1445641: Ignore SpeedCurve in-progress 403

SpeedCurve won't run a deploy if one is in progress. Detect as a
non-quite-success, not-quite-failure. Also, make the code more Python-3
compatible by using response.text, which should be decoded to unicode
automatically.

SphinxKnight/kuma,Elchi3/kuma,a2sheppy/kuma,a2sheppy/kuma,mozilla/kuma,escattone/kuma,mozilla/kuma,SphinxKnight/kuma,jwhitlock/kuma,jwhitlock/kuma,a2sheppy/kuma,jwhitlock/kuma,SphinxKnight/kuma,Elchi3/kuma,escattone/kuma,Elchi3/kuma,Elchi3/kuma,SphinxKnight/kuma,mozilla/kuma,jwhitlock/kuma,jwhitlock/kuma,SphinxKnight/kuma,escattone/kuma,mozilla/kuma,SphinxKnight/kuma,mozilla/kuma,a2sheppy/kuma,Elchi3/kuma,a2sheppy/kuma