Apply PSI to SplitNN training example

[TTitcombe]

Feature Description

Apply the PSI code to the SplitNN notebook to re-link vertically partitioned data. In its current state, the partitioned data is ordered, so PSI is unnecessary; change the arguments passed to the partition function to shuffle the partitioned data.

• Change the parameters passed to the partition function so partitioned data is unordered
• Demonstrate in the notebook that data is unordered i.e. print part of the data (this is not functional, but it helps to tell the story of what we're trying to achieve)
• Use the PSI code to re-order the data
• Train the SplitNN

Additional Context

Incorporating PSI into the SplitNN training example will finish the PoC
Do not work on this issue until #32 refactor is complete