Hyper-Parameter Optimization Framework - WIP

[D-McDougall]

@breznak,
As promised, here is my attempt at using NNI:
https://github.com/Microsoft/nni

I started from their MNIST example, and I modified the following files to work with Nupic:

• src/examples/mnist_nni/search_space.json
• src/examples/mnist_nni/config.yml
• src/examples/mnist_nni/mnist.py

I accidentally added the MNIST data files into git version control, so this branch is large and should never be merged to master :(

[breznak]

Perfect, thank you!
I'll add just FTR that this is an alternative to #433.

• I think we could pick the python version of SP MNIST you've implemented.
• the JSON with param space looks quite neat 👍

So one of the problems of this approach is lack of "default starting point params configuration"? Which is a failr choice, would make sense to put our so far best as a starting point.

[breznak]

Another hyper-param optimization framework, should support automated multithreading etc.
https://optuna.org/
Might look at, instead of our handwritten solution.