Add support for connections to Trino with TLS enabled

[Jimvin]

At present the Trino connection from Hue does not permit configuration of a trusted CA certificate, so connection to a TLS-enabled Trino coordinator is not possible. I've added support for passing the verify parameter to TrinoRequest so that a CA certificate can be configured. A user may also set verify=False to disable TLS host validation.

This was tested manually against a TLS-enabled Trino cluster:

• Connection to TLS enabled cluster with validate=False - client connection was successful
• Connection to TLS enabled cluster with validate not set - client connection failed as expected
• Connection to TLS enabled cluster with validate=/path/to/valid/ca.cert - client connection was successful

[agl29]

@Jimvin Thanks for your contributions, great work!
Could you please take care of a few additional points:

1. Add the verify parameter in trino section in both desktop/conf.dist/hue.ini and desktop/conf/pseudo-distributed.ini.tmpl
2. Define a default value for verify.
3. Add unit tests for this as well.