Changed directory structure.

Renamed DataSets/OCR/char to DataSets/OCR/characters and moved many
of the files from DataSets/OCR into this directory.
Modified code to use a larger data set and to fix some bugs that required
training and testing data sets to be the same size.
Changed from using MD5 hashes to using percentage and mean permanences
of connected and unconnected synapses for monitoring SP learning.

Added automatic determination of how many training cycles to run.
Created this class to enable parameter searches.  It can generate
combinations of the defined parameters either randomly or in order.
This is a data set that I created using LaTeX.  It is intended for
use in training the spatial pooler to recognize individual characters.