PUB-603: Only count rows during training.
PUB-603: Comment out TanhPrime.
PUB-603: Add support for per-column scaling factors during L2 computation.
PUB-603: Remove use of transposed matrices (and TanhPrime): Use full network instead.
Add helper function for auto-encoding back-prop for all activation
functions.
PUB-603: Compute reconstruction error and identify outliers with Quantiles.