Added simple programmatic test case.
Started filling in method stubs based on examples in Id3 classifier.
weka: Added method to retrieve leaf node corresponding to a particular instance.
Refactored to store tree structure as inner class Node objects.
Added code to keep track of per class/attribute/value counts for each node in vfdt/hoeffding tree.
weka: Continued implementing makeTree( Enumeration ) to make use of the new Count class.
weka: nodes keep track of the count for the largest class.
weka: renamed VFML class to more accurate VFDT and added javadoc comments.
weka: Added Hoeffding bound computation.
weka: finished entropy and information gain methods implementations.