CNN Visualization output

[jlinsley1983]

Need to fix the CNN Visualization output ability. Will be great to do comparison of death prediction versus live/dead status

[jlinsley1983]

CNN visualization is working, but only on a single neuron per time point per well. Need to be able to iterate over individual neurons within each neuron per time point per well.

Also, it will be great to use the GCAMP overlay ideas we did in the paper- ie to overlay the CNN gradient image on the GFP image and to set the scale on each image to be the same.

[drewlinsley]

Added these features but both need testing.