Make Survival Analysis Estimators consistent, and pass all required arguments

[eroell]

Description of feature

1. consistency
   E.g. tl.kmf operates on two arrays (see also Think about easier interface for KMF #387) while tl.nelson_aalen operates on an anndata.
   The latter should be the norm here if suitable.
2. passing all required arguments
   Then, e.g. tl.weibull doesnt take the entry column or any way to pass this to the fitter; harmonizing this to ensure all flexibility offered by lifelines is userfacing would be a great enhancement!

[eroell]

Can also make a suitable checkpoint list here together if it helps!

[aGuyLearning]

• Update Readme in Notebooks to include an installation command for locally cloned repos
• make method signatures uniform and kwargs
• update notebook example using kmf
• update documentation