Merge pull request #4 from philip30/master

Hiero Rule Extraction
Fixes to xBLEU tuning
A test and bug fixes for xBLEU tuning
Fixed an overflow in xBLEU
Added sentence level evaluation to mt-evaluator
Tuning of the scaling factor for xBLEU
Merge branch 'master' of github.com:neubig/travatar
Added L2 regularization over the weights
Fixed the gradient of weights using gamma
Made automatic scaling optional (off by default)
Prevent normalizing of scaling factor in xBLEU
Made the convergence conditions for lbfgs tighter
Made it possible to tune averageable measures
Added TER as an averageable measure
Fixed L2 regularization with scaling
Made an option for random restarts with xbleu
Improved efficiency of xeval
Added entropy regularization
Added parameters to batch-tune
Merge branch 'master' of github.com:neubig/travatar