Add classifiers and update contributing guide (#210)

CONTRIBUTING.md

@@ -30,19 +30,37 @@ encouraged to modify the codebase with new fixes and enhancements. Please
 observe the following guidelines when submitting pull requests for new fixes or
 features:
 
-1. All new code must comply with PEP 8. If you install Automata with
-`virtualenv`, the `flake8` package should already be available to you for this
-purpose. The only exception to this is that the maximum line length has been
-increased from 79 characters to 120 characters.
+1. All new code must comply with PEP 8, and be formatted with black and isort.
+If you install Automata with `virtualenv`, the `black`, `isort`, and `flake8`
+packages should be available to you for this purpose with the config in `pyproject.toml`.
+The included VSCode configuration is set to run this formatting on save.
+
+In addition, new code must include type annotations and pass typechecking run with
+[mypy](https://mypy.readthedocs.io/en/stable/).
 
 2. Whether you are introducing a bug fix or a new feature, you *must* add tests
 to verify that your code additions function correctly and break nothing else.
 
 3. Please run `coverage run -m nose2 && coverage report` and ensure that your
 changes are covered.
 
-4. If you are adding a new feature or changing behavior, I ask that you please
-update the README appropriately with the relevant documentation.
+4. If you are adding a new feature or changing behavior, please
+update the documentation appropriately with the relevant information. This
+includes updating docstrings for all functions in the public interface, using
+the [NumPy style](https://numpydoc.readthedocs.io/en/latest/format.html). To
+run the documentation site locally, install the documentation dependencies
+with:
+
+```sh
+pip install -r requirements.dev.txt
+```
+
+Then, start the local server with the following command:
+
+```sh
+mkdocs serve
+```
+
 
 ### Configuring a virtualenv
 

pyproject.toml

@@ -20,6 +20,19 @@ dependencies = [
     "cached_method>=0.1.0"
 ]
 
+classifiers = [
+    "Development Status :: 5 - Production/Stable",
+    "License :: OSI Approved :: MIT License",
+    "Programming Language :: Python :: 3.8",
+    "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
+    "Programming Language :: Python :: 3.12",
+    "Topic :: Scientific/Engineering :: Mathematics",
+    "Intended Audience :: Education",
+    "Intended Audience :: Science/Research",
+]
+
 # Per https://setuptools.pypa.io/en/latest/userguide/dependency_management.html#optional-dependencies
 [project.optional-dependencies]
 visual = ["coloraide>=1.8.2", "pygraphviz>=1.10"]