Add deferrable analysis template once analyzers are better organized

[Guy-L]

something like

class DeferrableAnalysis(Analysis, ABC):
    deferred = False
    history = []

    def step(self, state):
        if deferred:
            history.append(state)
        else:
            self.process(state)

    def done(self):
        if deferred:
            for state in history:
                self.process(state)

         #to be extended

    @abstractmethod
    def process(self, state):
        pass