Vendored version of backports.ssl_match_hostname and use it as a fallback in case match_hostname isn't present in either the stdlib or a backports.ssl_match_hostname pypi module.
Make a note of ssl_match_hostname being under the PSF license
Fix cut and paste error
Fix unittest to import the correct CertificateError
Revert "Fix unittest to import the correct CertificateError"

This reverts commit e663b3c077e01bc0f5a33ffb87c18173c2c1b6f7.
Revert "Fix cut and paste error"

This reverts commit fa73693a0f44bba05ec916f19e09bc68cb1b6007.
Revert the old method of choosing which ssl_math_hostname module to use.
Implement checking of which match_hostname function to use inside of the packages module.
Correct cut and paste error again
Merge pull request #274 from abadger/feature/vendored-backports-ssl_match_hostname

Feature/vendored backports ssl match hostname