Rudder

We can do this in 3 steps:
- tag generic methods that are not convergent
- expose this tag via the API
- display non convergence in the editor

A non convergent call is a call to a non convergent method:
- without condition
- or with an always true or always false condition (any, OS based)
- or with a success based condition (method_call_kept)

Since conditions can be any combination of class we should limit ourself to simplistic form (a single class).