add plumbing for evaluating features that need source sentence
make evaluation of TargetWordInsertionFeature more efficient. It's a normal stateless feature, was evaluating at every hypothesis expansion
delete unused function
Merge branch 'master' of github.com:moses-smt/mosesdecoder
optimise evalution with SourceWordDeletionFeature
optimise evalution with SourceWordDeletionFeature
optimise evaluation with sparse features
optimise evaluation with PhraseLengthFeature