simplify awxkit dependencies

- remove flake8 as an install requirements (it's only used for tests)
- vendor toposort, which is Apache 2.0 licensed (and very small)
- change websocket-client to a setuptools optional dependency, which you
  can install via:

  pip install "./awxkit[websockets]"

- add `jq` and `tabulate` under an additional optional setuptools
  dependency:

  pip install "./awxkit[formatting]"

- remove `cryptography`, which is only used for random RSA generation
  (unused by the CLI)

awxkit/setup.py

@@ -68,6 +68,10 @@ setup(
     include_package_data=True,
     install_requires=requirements,
     python_requires=">= 3.5",
+    extras_require={
+        'formatting': ['jq', 'tabulate'],
+        'websockets': ['websocket-client>0.54.0'],
+    },
     entry_points={
         'console_scripts': [
             'akit=awxkit.scripts.basic_session:load_interactive',