CHANGES IN 'FGN' VERSION 2.0-5 (2013-04-02)
    o    improved compatibility with FitAR and arfima 
CHANGES IN 'FGN' VERSION 2.0-3 (2013-03-11)
    o    ACM license, restricts to academic use
CHANGES IN 'FGN' VERSION 2.0-2 (2013-03-10)
    o    added warfima, earfima, WLoglikelihood, sdfhd, sdfarma, Series B, globtp
CHANGES IN 'FGN' VERSION 2.0 (2012-09-06)
    o    citation revised
    o    new functions for HD and FD models
CHANGES IN 'FGN' VERSION 1.4 (2010-11-30)
    o    fixed NAMESPACE problem