Autodocsumm

This release improves the implementation of autodocsumm by generating the tables using the `.. autosummary` directive. This solves multiple ambiguities within the package. We furthermore add new options:

- `:autosummary-sections:` to select specific sections to generate the autosummary tables for
- `:autosummary-no-titles` to omit section titles

Furthermore this release adds the `.. autoclasssumm::` and `.. automodulesumm::` directives to generate the autosummary tables anywhere in the documentation.

Minor fix with reference to https://github.com/Chilipp/autodocsumm/issues/24 and https://github.com/Chilipp/autodocsumm/pull/25 to not use the `Autosummary.warning` attribute.

This patch makes autodocsumm compatible with sphinx 2.4.0.

Thanks to the work by piyushk in https://github.com/Chilipp/autodocsumm/issues/19, autodocsumm now has a `:autosummary-no-nesting:` option to disable the generation of autosummary tables for the classes in a module.
As such,

.. automodule:: module
:autosummary:
:members:
:autosummary-no-nesting:

will generate an autosummary table for the specified `module`, but not for the members (i.e. classes) in the module.

See the [docs for an example](https://autodocsumm.readthedocs.io/en/latest/examples.html#generating-a-summary-table-for-the-module-without-nesting).

This new releases solves the bug from https://github.com/Chilipp/autodocsumm/issues/8 to properly name instance attributes in the autosummary table. Thanks maeddlae for reporting.

Thanks to coldfix, autodocsumm has now better support for cython files and a better documentation.
See the PRs https://github.com/Chilipp/autodocsumm/pull/4, https://github.com/Chilipp/autodocsumm/pull/5 and https://github.com/Chilipp/autodocsumm/pull/6.