Update httplib2 version to incorporate https://github.com/jcgregorio/httplib2/pull/313
Update httplib2 version to incorporate https://github.com/jcgregorio/httplib2/pull/313

googledatalab/datalab,googledatalab/datalab,googledatalab/datalab,parthea/datalab,parthea/datalab,craigcitro/datalab,yebrahim/datalab,yebrahim/datalab,googledatalab/datalab,googledatalab/datalab,parthea/datalab,yebrahim/datalab,yebrahim/datalab,googledatalab/datalab,craigcitro/datalab,parthea/datalab,craigcitro/datalab,parthea/datalab,craigcitro/datalab,parthea/datalab,yebrahim/datalab,craigcitro/datalab