Better, easier, and integrated support for color bars

[tpvasconcelos]

Add better support for easier and integrated color bars!

Usually this is achieved with layout.coloraxis.colorbar but I'm not sure how easy it is for users to manually integrate this with our ridgeplots. At least add an example to the docs? (REF1)

Refs:

• https://plotly.com/python/colorscales/#customizing-tick-text-on-discrete-color-bars
• https://plotly.com/python/colorscales/#using-label-aliases-on-colorbars
• https://plotly.com/python/colorscales/#positioning-colorbars