README and LICENSE
 * Clarified some points in the README
 * Added WTFPL as a license for NlpTools
Improvements
 * Speed improvement in maxent_grad_descent.php
 * Added training report in grad_descent.php (so that one
   doesn't stare at a blank screen while training)
 * Some comment changes and clarifications
Added Stemmers
 * Added a Stemmer interface
 * Added a simple regex stemmer
 * Added a fast porter stemmer (see stemmers/porter_stemmer.php
   head comment for details)
 * Added tests for porter stemmer and benchmark (also this way
   of adding tests should probably be followed instead of
   everything in a single folder)

TODO:
Update README with new content and add more stemmers
(perhaps Snowball and definitely a Greek one)