update changelog
update changelog

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