* Refactored (un)registerListener methods to use overloaded methods instead
  of the original single method with a bunch of ugly if statements within.
* Refactored in order to remove all uses of 'supportService' calls which were
  just poor design.
* Flattened unnecessary namespace hierarchy.
* Removed the #pragma macro for visibility.  SAL_DLLPUBLIC_EXPORT is used
  instead.
* Modified LU factorization routine to use another algorithm that seems more
  robust than the one being replaced.

2005-12-6	rev. 100
* Improved LP model builder algorithm to remove decision variables with zero
  cost and zero constraint column.
* Refactored LpModelBuilderImpl class to use fewer member variables.
* Fixed over-reduction of column size in the two phase simplex routine by
  allowing basic variable(s) to have zero value (a.k.a. degeneracy).

2005-11-22	rev. 90
* Implemented more efficient matrix inversion algorithm by way of LU 
  factorization.  This should totally eliminate the "freeze" issue present 
  in the current Revised Simplex implementation.  The previous fix was not
  effective in all cases.
* Fixed bug in loading a model from document (it did not clear constraints 
  before appending new ones).
* Implemented reset function.

2005-11-6	rev. 86
* Added support for loading and saving a model with a current document.
* Significant performance improvement on inverse matrix calculation for 
  sparse matrix.  This should speed up many linear model scenarios where it
  previously caused a "freeze".

2005-10-30	rev. 81
* Support for defining multiple constraints from cell ranges.
* Removed Python prototype code (internal).
* Reorganized file hierarchy structure (internal).
* Ported Quasi-Newton non-linear algorithm (BFGS) from its original Python 
  code.  But this algorithm cannot be invoked from the UI yet (internal).

2005-9-24	rev. 71
* Completed implementation of Revised Simplex algorithm for solving a 
  constrained linear model.


