Add square-root scale for plotly and bokeh

[aloctavodia]

For the rootogram we need to transform the y-axis to the square-root scale. This is already implemented for matplotlib backend but not for the rest.

[The-Broken-Keyboard]

@aloctavodia assign it to me, I will do it

[The-Broken-Keyboard]

@aloctavodia to implement square root scale in Bokeh, it requires to add a typescript or javascript file because that's the only possible way to add custom scale in Bokeh. Is it fine to add typescript file for scaling in Bokeh backend folder.

[aloctavodia]

Not sure, probably OK.