added changeable cutoff value
output layer updates
weight masks
removing commented out code
fixes to ZFeedForwardNet

-means and stddevs no longer include -999
-removed erroneous “tanh transform” - it was just wrong and unnecessary
-values of -999 are now transformed to column mean in to_zscores
(results in zscore of 0)
cleanup, minor tweaks
cleanup, cutoff searching (BIG WIN!)
halfbaked starting code for denoising autoencoders
EventId index, ams improvements