Compute and display data completeness for every station/channel on heatmaps

for the display part see :

• https://plotly.com/python/multiple-axes/
• https://plotly.com/python/table-subplots/
• https://plotly.com/python/marginal-plots/ ?
• https://stackoverflow.com/questions/75002870/adding-a-secondary-y-axis-on-heatmap-in-plotly-express-python
• https://maegul.gitbooks.io/resguides-plotly/content/content/plotting_locally_and_offline/python/multiple_axes_and_subplots.html

and for the processing part :

• https://numpy.org/doc/stable/reference/generated/numpy.mean.html#numpy.mean
• np.mean(results[:,:,0], axis=1) seems to work