Merge Debugger support with cell hashing code

[IanMatthewHuff]

Merge the debugging support and the shell hashing code to work together to correctly map jupyter execution to .py file breakpoints.

[YoniChechik]

Does it means that one can debug with breakpoints in interactive mode?

[IanMatthewHuff]

@YoniChechik . Debugging as an overall goal is currently in progress right now. Currently we support the very basics of debugging (attaching the debugger, you can hit a breakpoint() in cell code) but we don't currently map anything back to source files so debugger break points in code will not currently be hit and when you break in the debugger you will just see a temporary file of the cell code that you sent to jupyter. The work that we are currently doing now, but is not checked in, is to make that .py file line -> jupyter code cell mapping so that you can place breakpoints in your .py code and hit them.