Added and tested code to support an alternate S3 server to make testing easier.  Added code to delete partial uploads.
Added and tested code to support an alternate S3 server to make testing easier.  Added code to delete partial uploads.

sutartmelson/girder,girder/girder,Kitware/girder,opadron/girder,msmolens/girder,salamb/girder,opadron/girder,jcfr/girder,jbeezley/girder,essamjoubori/girder,data-exp-lab/girder,msmolens/girder,manthey/girder,jbeezley/girder,girder/girder,Kitware/girder,jcfr/girder,salamb/girder,data-exp-lab/girder,Xarthisius/girder,essamjoubori/girder,jcfr/girder,manthey/girder,chrismattmann/girder,girder/girder,essamjoubori/girder,sutartmelson/girder,RafaelPalomar/girder,Kitware/girder,chrismattmann/girder,adsorensen/girder,chrismattmann/girder,msmolens/girder,chrismattmann/girder,msmolens/girder,sutartmelson/girder,kotfic/girder,essamjoubori/girder,jbeezley/girder,kotfic/girder,kotfic/girder,msmolens/girder,salamb/girder,adsorensen/girder,RafaelPalomar/girder,opadron/girder,salamb/girder,kotfic/girder,essamjoubori/girder,adsorensen/girder,RafaelPalomar/girder,jbeezley/girder,jcfr/girder,jcfr/girder,kotfic/girder,opadron/girder,chrismattmann/girder,sutartmelson/girder,manthey/girder,RafaelPalomar/girder,manthey/girder,adsorensen/girder,opadron/girder,Xarthisius/girder,adsorensen/girder,girder/girder,Xarthisius/girder,data-exp-lab/girder,salamb/girder,data-exp-lab/girder,sutartmelson/girder,data-exp-lab/girder,Xarthisius/girder,Kitware/girder,Xarthisius/girder,RafaelPalomar/girder