Normalize Input Data

[johnmartinsson]

Input data should have zero mean and identity variance.

Note: mean, and variance should be computed from the training set ONLY, and then subtracted from the training, validation and test sets.

http:https://cs231n.github.io/neural-networks-2/#datapre

[johnmartinsson]

This functionality should be left out for now. But it may be interesting to consider later in the project. Moved to the next milestone.

[johnmartinsson]

This could be considered in the future, but will not be part of the thesis work. Removed from milestone.