Add Spark support

[alondhe]

Is your feature request related to a problem? Please describe.
Recently, we've added Spark SQL support to SqlRender and a few OHDSI tools. We'd like to do the same for WhiteRabbit.

Describe the solution you'd like
My team will raise a PR to add Spark, with the necessary JDBC connection string format, as well as any SQL translations needed.

Describe alternatives you've considered
We don't have any other database platforms, so we'd need this added in order to use the tool.

Additional context
None

[zwelshman]

@alondhe I'm particularly interested in a SparkSQL/PySpark implementation. Is there anything I can help with?

[natb1]

Something like this would be needed to enable OHDSI/Perseus#11 I will try to get more information via teams. @zwelshman depending on the existing progress, is this something you would be interested in working together on?