Version 2.1 (07 Mar 2016)
   * improved documentation	;
   * fixed a problem with thetaModel class;	


Version 2.0 (29 Feb 2016)
   * included the models: dotm, dstm, otm, stm, stheta, expSmoot;
   * included the class thetaModel;
   * included S3 functions: plot.thetaModel, print.thetaModel, summary.thetaModel;
   * the old otm() function was renamed to otm.arxiv();
   * the thetaM() function was replaced by stheta() for equivalence with IJF paper;
   

Version 1.1 (31 Jul 2015)
   * NAMESPACE updated;
   * otm() updated;


Version 1.0 (15 Apr 2015)
