Display docstrings defined in parent class methods for child classes

[jklaise]

We should go over the API docs and check that everything is rendered and documented correctly. Additionally, there are a bunch of methods and functions which should be made private and not show up on API docs as a result (e.g. build_explanation).

Special attention should be paid to to display docstrings defined in parent class methods which are not overridden by subclasses. This may require some sphinx investigations.

This includes #229 but has broader scope.

[jklaise]

API docs audit is done as part of #548. Renaming the issue to still consider the more minor issue of having parent class docstrings to show up in child-classes.