removed workaround for no https proxy support, since we now carry python-requests-2.0.0 which includes updated urlllib3 and provides the https proxy support
we need to set both the 'http' and 'https' protocols to '://'.join((protocol, url))
updating revent downloader with the latest change in threaded downloader since it is generally maintained in lock-step with the threaded downloader
Merge pull request #11 from pulp/skarmark-1014368

removed workaround for no https proxy support, since we now carry python...