The 20 News Groups Collection Will be Converted Into ARFF

The 20 News Groups collection will be converted into a single ARFF file.
The majority of the special characters will be removed. Also, tokenizing
will have it's own method so that all the document collections are
treated the same. Interface has been updated to use the new code.
Fix Interface Reset Bug

There is a bug in Interface that does not let you process more than one
document collection per instance.
The 20 News Groups Collections Can be Clustered