Split usage-python into basic and advanced part

While working on !305, I noticed that our basic usage example is quite long and contains some advanced options and doubled information that might be too much for a new user. I suggest we split the example into a very short basic usage example, an advanced usage and remove some sections

Into the advanced we can move the sections

• Uncertainity estimates
• Additional Options
• Improving the Results including a new section on the AnalysisCollection

and show it these the How-to guides section in our documentation.

Once we also have the examples from the paper I suggest removing the Velocity Profile and Water average orientation section. They don't teach any new syntax or options and might therefore superfluous here.