- Added class TrustRegionMinimizer for solving both constrained and
  unconstrained nonlinear least squares problems using the Trust Region method,
  a variant of the Levenberg-Marquardt method.  
- Added class OneVariableFunctionFitter for fitting generalized one variable
  functions to data. 
- Added class MultiVariableFunctionFitter for fitting generalized multivariable
  functions to data.
- Organized classes into solution folders inside Visual Studio.
- Added VS 2008 solutions for all examples and source editions.
- Added Add(System.Object) method to all types which implement IEnumerable.