Changes in version 1.2.1                        

  - Allow analysis of directed graphs and add four new centrality
    measures specific for the directed graphs.
  - Modify annotation functions to allow annotate nodes not only by its
    name propety but by any other arbitrary property if its value
    uniquely identify the node.
  - Added new framework for the visualisation and analysis of enrichment
    results.

                      Changes in version 0.99.001                       

  - Added a NEWS.md file to track changes to the package.