Make waterdynamics stop behaviour the same as AnalysisBase

[IAlibay]

Is your feature request related to a problem?

As detailed in MDAnalysis/mdanalysis#2525 (comment) several waterdynamics methods currently have an inclusive tf (i.e. final frame) behaviour instead of the exclusive behaviour exhibited by AnalysisBase's stop. In order to offer users a consistent API, it would be advantageous to make everything exclusive.

Describe the solution you'd like

Change the behaviour of the final frame definitions in waterdynamics to be exclusive.

Describe alternatives you've considered

The ideal alternative here is to switch waterdynamics over to AnalysisBase.

Additional context

PR MDAnalysis/mdanalysis#2525

[PicoCentauri]

I'm already working on the Analysis modules. I will move them to AnalysisBase.

[hmacdope]

Im going to add this to 3.0 as fits in thematically with MDAnalysis/mdanalysis#3893