text: Title: API Discussion for Figures and Axes
  Body: This issue is to discuss the open letter regarding Yellowbrick's API roadmap. To summarize, we currently attempt to only manage matplotlib `Axes` objects so that visualizers can be embedded into more complex plots and reports. However, many of our visualizers are getting increasingly complex, requiring subplots of their own. For a complete discussion of the API issue please see:
  
  https://www.scikit-yb.org/en/develop/api/figures.html
  
  The questions at hand are:
  
  1. Like Seaborn, should YB have two classes of visualizer, one that wraps an axes and one that wraps a figure?
  2. Should we go all in on the AxesGrid toolkit and continue to restrict our use of the figure, will this method be supported in the long run?