Updates anomaly docstrings

[rhyolight]

WIP

fixes #3536

[marionleborgne]

LGTM 👍 . Just one question, to make sure you did not delete something by mistake.

[marionleborgne]

Why did you remove the doc string in the init?

[rhyolight]

I have been moving all init docs into the class docs because it works better with Sphinx.

[scottpurdy]

We should have good doc strings for __init__ functions. Usually the only info you need here is the parameter documentation. But I don't think we should move that to the class doc string just because of docs tooling.

[rhyolight]

@scottpurdy Can I add a docstring in each __init__ that points to the class definition? This seems like a common convention in python projects using Sphinx.

[scottpurdy]

After looking into the Sphinx issue, I don't have a strong opinion. You might want to check with others since this is something all engineers will have to be aware of. But I'm fine with whatever route you want to go.