Changes to Version 0.7-0

   o Fixed problem with analytic gradient, which caused convergence problems for some models.

   o Simplified optimization.

   o Added modification indices (preliminary version).
    
   o Some changes to start values.
    
   o Added RMSEA to fit indices. 
   
   o Added Klein dataset. 
   
Changes to Version 0.7-1

   o Replaced F with FALSE as logical, F with f as variable.
   
Changes to Version 0.7-2

   o Fixed tsls examples to run even if a global variable named F exists.
   
Changes to Version 0.7-3

   o Fixed bug in start-values routine that affected unstandardized models.
   
   o Added code to try to detect under-identified models.
   
