Fixes for DictColumns array, sort, groupby and aggregate methods
Fixes for DictColumns array, sort, groupby and aggregate methods

ioam/holoviews,vascotenner/holoviews,basnijholt/holoviews,vascotenner/holoviews,ioam/holoviews,vascotenner/holoviews,ioam/holoviews,basnijholt/holoviews,basnijholt/holoviews