Bug 885331 - added PYTHONPATH in doPartnerRepacks env. r=nthomas

--HG--
extra : amend_source : 48a0f5ea7deae4f0ab50e59845f2c3275fb19ab9
Bug 1074826 - Clean up some pyflakes & PEP8 warnings in buildbotcustom; r=pmoore
Merge branch 'master' into fx-mh-builds
Merge branch 'fx-mh-builds' into fx-mh-builds-dev