Add s3fs to requirements (#1316)
Add s3fs to requirements (#1316)


cpcloud/dask,mraspaud/dask,blaze/dask,mrocklin/dask,jakirkham/dask,dask/dask,mraspaud/dask,mrocklin/dask,chrisbarber/dask,jcrist/dask,dask/dask,ContinuumIO/dask,blaze/dask,gameduell/dask,jcrist/dask,cowlicks/dask,ContinuumIO/dask,jakirkham/dask