Recognition System (still buggy) which determines "example-ness"
by clustering based on responses to filters. Includes Pattern
(responses to filters used for clustering),
Cluster (combination of Patterns), ClusTree (clustering
using nearest-neighbor trees), Image (ppm file reader),
GausImage (image on multiple scales for multidimensional
pattern recognition), Histogram (a collection of clusters for
statistical analysis; contains multiple clustering algorithms),
Model (multiple histograms describe a class of images), and
System (a combination of models for classifying an image), and
Cluster data file I/O.