Add jdbc connection params when needed

[joel-bernstein]

The jdbc Streaming Expression requires jdbc connection parameters to be supplied. There are a number of reasons that this is not desirable from inside Zeppelin paragraphs. One reason is it creates noise in the code and needless repetition. The other issues is that sharing notebook code automatically means sharing jdbc connection parameters.

This ticket allows for configuration of the jdbc connection params as part of the interpreter config. The initial release of this is for convenience and improved usability of the jdbc Streaming Expression with the Zeppelin-solr interpreter. Security has not been addressed in this PR and will be addressed in future PR's.

[joel-bernstein]

Sample of jdbc calls made without connection info specified.

[joel-bernstein]

Screenshot of configuration