use plain http instead of ssh+git for polling refspecs
use plain http instead of ssh+git for polling refspecs

vaporry/ethereum-buildbot,ethereum/ethereum-buildbot,chfast/ethereum-buildbot,vaporry/ethereum-buildbot,chfast/ethereum-buildbot,ethereum/ethereum-buildbot,chfast/ethereum-buildbot,vaporry/ethereum-buildbot,ethereum/ethereum-buildbot