Lat/lon labels about geoviews

[philippjfr]

Adding nice tick formatting for mercator coordinates will be supported in bokeh very soon: bokeh/bokeh#6017. We should make use of it for all geographic bokeh plots.

[philippjfr]

This has finally been implemented, closing.

[zxdawn]

@philippjfr The formatter doesn't work well. As you can see in the Tick formatters section of this tutorial.:

def formatter(value):
    return str(value) + ' days'

curve.relabel('Tick formatters').opts(xformatter=formatter, yformatter='$%.2f', width=500)

But the xaxis ticks still keep same. So, I want to get the degree symbol on ticks like @kthyng said before, how to add it?