WeightsSet: Experimental new methods sparsify() and densify().
DocumentAnnotator: More clear error message when there are conflicting post/prereqs.
LoadConll2003: Clean up old unused code.
LoadPlainText: New facility for loading more than one Document from the same file, using documentSeparator regex.
WeightsSet: Simplify sparsify().
deserialize: allow substitution of Tensor dense/sparse type.
Tensor.newSparse: handle t:DenseLayeredTensor2.
SparseIndexedTensor.+=(Int,Double): If Double is 0.0, do nothing, preserving more sparsity.
NLP, POS1,3,NER12,3,DepParser1: Convert to use URLs to specify model loading locations.
Merge.
Fix various warnings.
relations: better features, separate label from mention
relations: support for sub types