Add a diagram explaining the lifecycle methods and hooks

[phillipskevin]

It would be useful to add a diagram that explains the StacheElement lifecycle methods and hooks:

This could explain which methods are called by the browser, the flow through our methods, and when user-defined hooks are called.

[phillipskevin]

There are many of these for React, such as https://twitter.com/dan_abramov/status/981712092611989509.