* Add skip when required TLS version unsupported
Allow tests to skip, rather than fail from SSL errors with unsupported
TLS version, e.g. if Openssl is configured with MinProtocol higher than
the version being tested.
* Regenerate test certificate and key
Regenerate these with more secure settings for the sake of future
proofing, regenerate the key using RSA 4096 and sign the certificate
with SHA512.
This fixes test failures in tests/test_ssl.py when the user's OpenSSL
security level is set to a value greater than 1 and resolves issue #948
* Suppress SSL warnings in no verify tests
* Add test to test auth plugin reused in session
* Remove unnecessary assertion in auth-plugin test
* Fixed auth test to use same session file
* Add test for password prompt behaviour in session
* Edit auth readme for plugin clarity
* Added a sub-section specifically for windows
* Wrote instructions for creating/activating venv
* Split the PS and CMD examples into two separate code blocks
* Specified language for the code blocks
* Added test instructions for windows
* Converted slash to backward
* Removed the instructions of tox testing
* Deleted tox.ini
* removed tox from requirements
* removed tox from setup.cfg
* removed tox from the Makefile
* removed tox from contributing docs
* updated the CHANGELOG
* removed tox from .gitignore
