added support for encoding parameter to bag.from_textfiles
added support for encoding parameter to bag.from_textfiles

pombredanne/dask,vikhyat/dask,ContinuumIO/dask,dask/dask,blaze/dask,PhE/dask,ssanderson/dask,mraspaud/dask,jcrist/dask,ContinuumIO/dask,cowlicks/dask,blaze/dask,chrisbarber/dask,cpcloud/dask,gameduell/dask,vikhyat/dask,dask/dask,ssanderson/dask,jakirkham/dask,mrocklin/dask,jcrist/dask,clarkfitzg/dask,PhE/dask,clarkfitzg/dask,jakirkham/dask,mrocklin/dask,mikegraham/dask,pombredanne/dask,mraspaud/dask