Changes in version 0.15 (2018-11-10)                  

  - Substantial speed increase by fixing the possible embedding
    dimensionalities to 1, 2 or 3
  - Clarification of the licensing of different parts of the package
  - Support for using, more efficient, partial PCA (by Daniel Wells)
  - Made the normalization optional and the normalization function used
    available (by Aaron Lun)
  - Support for using precomputed nearest neighbour matrices (by Aaron
    Lun)
  - Added OpenMP support
  - Default verbose value is now the global setting (by Richard Cotton)
  - Added a NEWS.md file to track changes to the package.