2011-08-12 Pedro Canadilla <pedro.canadilla@gmail.com>

    * Fixed B-erlang and C-erlang functions to have defaults values and to check values.

    * Fixed extreme value of Pn in M/M/1/K/K model.

    * More detailed documentation has been created for the saturation point in the M/M/1/K/K model. The optimal number of clients (or saturation) point coincides with the inverse of the serialization parameter of Amdalh's Law. That is, the value which converges the speedup function k/(1 + ser(k-1)). It makes sense, because the saturation point is the maximun value in which no syncronization happens.

    * Fixed in the M/M/1/K/K model the Pn function. It was returning RO instead of Pn.

    * Fixed and improved the model M/M/c. The parameter n was not working as needed.

    * Included a new parameter method which controls if the probabilities are calculated exactly or if an aproximation is used in models M/M/1/K/K, M/M/C/K/K, M/M/C/K/M, M/M/C. The aprox method are useful to get the model work with higher parameter values.

    * Fixed also the parameter n in models M/M/1, M/M/C and M/M/Inf. With n=-1, no probabilities are calculated. 

    * Documented the resolution of a Open Jackson Network with visit ratios instead of probabilities.

    * Added the node of type M/M/Inf (or delay node in the literature) in the Open Jackson Network.

    * Added the model M/M/Inf/K/K.

    * Added more examples in the documentation of Open Jackson Models and Closed Jackson Model to use visit ratios.

    * Fixed a bug in Closed Jackson Network with several nodes of class M/M/C

    * Added the Multi Class Open Network model.

    * Fixed some doc, W in the Open Jackson Network.

    * Top level Copying file deleted.

    * removed is.nan(x) just because of CRAN checks. 

