Included create_ssl_context function to create the same context with SSLConfig and...

Included create_ssl_context function to create the same context with SSLConfig and serve as API (#996)

* Included create_ssl_context function to create the same context with SSLConfig and serve as API.

* Changed create_ssl_context with SSLConfig into the client implementation and tests.

* Dropped the __repr__ and __eq__ methods from SSLConfig and removed SSLConfig using from tests

* Fixed test issue regarding cert_authority trust of ssl context

Co-authored-by: Tom Christie <tom@tomchristie.com>
Co-authored-by: Florimond Manca <florimond.manca@gmail.com>