add _easy_facetgrid helper function for plots
add _easy_facetgrid helper function for plots

rabernat/xray,shoyer/xarray,shoyer/xarray,pydata/xarray,jhamman/xarray,petercable/xray,jhamman/xarray,rabernat/xray,markelg/xray,NicWayand/xray,chunweiyuan/xarray,pydata/xarray,jhamman/xarray,jhamman/xray,cpaulik/xray,jcmgray/xarray,drewokane/xray,markelg/xray,markelg/xray,xray/xray,pydata/xarray,cpaulik/xray,shoyer/xray