New features:
- Lorentz manifold implementation
- New model module which currently contains one model which is an implementation of Poincare Embeddings for Learning Hierarchical Representations called HierarchicalEmbeddings
- New loss function module which contains implementation of loss function which can be used for HierarchicalEmbeddings model (and other uses)
- New WordNet embeddings example using HierarchicalEmbeddings model