Docs do not show base classes

[erastorgueva-nv]

I just noticed that our docs do not show inheritance, though src/conf.py has 'show-inheritance': True. Would be nice to fix. So that we can see if the class inherits from BaseParallelProcessor or directly from BaseProcessor.

cc @Kipok, @karpnv

[Kipok]

If you want to do that, just add directly :show-inheritance: to those classes in the rst file. Note how it's done at the end for the base classes - they do show inheritance. When I was originally writing that doc, I decided that showing base classes would complicate things as I was mostly thinking of that page as a "config-level" guide for users. That is, for people who are just building new configs based on the existing processors, it can be very useful to see all processors and their parameters, but they don't really need to know inheritance or see all the methods of those classes.