new release:
- The function DEoptim has the new argument 'initial', which is an initial or starting population.
  You can therefore introduce a starting population in the optimization procedure. This can be useful
  when the optimization has to be run many times on data sets which differ sligthly. Thanks to
  Tarmo Leinonen for this nice suggestion.

- The function DEoptim outputs now 'pop' in the 'member' list's element. This is the population obtained
  at the last iteration which can be used as a starting population in DEoptim via the argument 'initial'.
  
- The function stops if any 'NA' or 'NaN' value is returned by the function 'FUN' to be optimized.

- The function DEoptim does not handle exponential crossover anymore. This is so to simplify and
  accelerate the optimization procedure. Thanks to Vladimir Eremeev for pointing out a 
  bug with the exponential crossover.

- The function DEoptim outputs a list of lists. This is more natural and in the same spirit 
  of usual optimization functions. Thanks to Vladimir Eremeev for proposing this change.
  
- documentation for the 'digits'. Thanks to Eugene Demidenko for pointing out this.

2007/02/02:
- The documentation of DEoptim has been modified. Corrections of some references.