GC-91: Adding new implementations/ports for two new versions of the L-BFGS optimizer:
 - The updated bounded optimizer available in Lbfgsb.3.0, and
 - The updated L-BFGS library with support for Orthant-Wise optimizer in LibBFGS.

Several tests still have to be implemented and the interfaces must be corrected to try avoiding breaking changes.
GC-91: Adding several new unit tests and a testing framework for comparing the LibBFGS implementation against the framework sources.

More tests are still needed for the bounded L-BFGS sources.
GC-91: Linking the original Lbfgsb3 library against the unit tests project in order to write more unit tests for the BoundedBroydenFletcherGoldfarbShanno optimizer.
GC-91: Starting to get the first Lbfgsb3 tests working.
GC-91: Lbfgsb3 tests now work.
fixed calculation of position when sampleIndex is set in WindowBase#Apply method
GC-91: Working on documentation, normalizing optimizers interfaces and preparing room for GC-63.
GC-91: Refactoring of the function optimization methods. Optimization methods don't throw exceptions anymore.
GC-91: Working on unit tests and documentation.
Fixing Codification filter issue when one of the processed columns have a max-length constraint.
Merge pull request #2 from webner/development

Fixed calculation of array position when sampleIndex is set in WindowBase#Apply
Merge remote-tracking branch 'upstream/development' into development
Merge branch 'development' into portable

Conflicts:
	Sources/Accord.Core/Extensions.cs
	Sources/Accord.Tests/Accord.Tests.Statistics/Filters/CodificationFilterTest.cs
Adaptations to make the new code build and unit tests pass

Audio.ComplexSignalTest.ComplexSignalConstructor currently fails in
WindowsBase.Apply; AccessViolationException