Update README.md
correctly compute running mean and variance of feature vectors
Merge remote-tracking branch 'upstream/pydecode' into pydecode
Exit with helpful error on missing labels in training set
Fill trellis with zeros before using. Decoding of previous sentences may have left in -INFINITY values if constraints were used
Merge remote-tracking branch 'upstream/pydecode' into pydecode
Merge remote-tracking branch 'upstream/master' into pydecode