GFF manipulation.

GFF is a text-file format for specifying features within sequences. For up-to-date information, go to the GFF home page. Using this package, you can load GFF from a stream, create Features on Sequences, generate GFF from Features and write GFF to file.

Nearly all of the API uses the concept of a GFF stream that 'pushes' GFF from some source to a recipient. Recipients implement the GFFDocumentHandler interface.

There should be some demonstration programs in the `biojava-live/demos/gff` directory.