develop and integrate interface for persistent kernels

[jmorwick]

these kernels will have queriable state and can support debugging

[jmorwick]

Determine if there is an important difference with codelens (using plugins below) and whether to integrate or kill feature:

https://github.com/daveagp/java_jail/tree/master/cp/traceprinter

https://github.com/daveagp/java_visualize