Use a case class for SVD instead of a tuple
case classification of QR/eig/etc
generification of several FeatureVector ops
transpose multiplicaiton for feature vectors
remove scalalogging
Merge pull request #288 from mengxr/remove-scalalogging

remove scalalogging from dependencies
improved the interface for checking convergence in the optimizers.

You can now ask for min.minimizeAndReturnState instead, and that
will give you a state object with a .convergenceReason

fixes #250
Merge remote-tracking branch 'scalanlp/master'