Add SSL Cassandra support

[robertdkmarshall]

What is this PR for?

The Cassandra Interpreter does not support talking to clusters that use SSL/client to node encryption. It does not have the properties needed to configure the SSL Context. This PR adds the properties to the driver config and sets up the ssl options when they are requested.

What type of PR is it?

Improvement

Todos

• - Task

What is the Jira issue?

https://issues.apache.org/jira/browse/ZEPPELIN-1501

How should this be tested?

Using CQL interpreter connect to a Cassandra cluster that uses client to node encryption.

Screenshots (if appropriate)

N/A

Questions:

• Does the licenses files need update? No
• Is there breaking changes for older versions? No
• Does this need documentation? Yes. Should add the new properties to the list (cassandra.ssl.enabled, cassandra.ssl.truststore.path and cassandra.ssl.truststore.password).

[Leemoonsoo]

\cc @doanduyhai

[doanduyhai]

Ping @robertdkmarshall, any new from my code review ?

[doanduyhai]

Without feedback I'll push a new PR with suggested code refactor & merge it in a few weeks @robertdkmarshall,

[jcam3ron]

Any update on whether this might be merged soon?

[doanduyhai]

Let me redo the PR and merge with the above remarks included