Provide configuration option to set a custom Certificate Authority or use the OS keystore

[C45p31]

Some use cases involve self signed certificates for jira or any kind of reverse proxy in front of Jira server. Since Jira/ib/jira/client.py has for a good reason, Verify = True, I believe it would make sense to make this option available in the package config to be able to either specify False or the path to a different CA, or completely different, attempt to use the OS keystore to retrieve the CAs. Best case scenario would be to implement both, in which case, the configuration will overwrite all other SSL Verify settings and force the value set in the config.

[gerhard-tinned]

I would need this setting too.