OSX, Xcode 5 project files, linux support

This pull request contains the following changes:

* Inclusion of @tgjones 's commit for vs2010 project files
* Separation of project files into meaningful sub directories
* Merges to support compilation on Linux and OSX from linux branch
* Updated makefile to support Linux and OSX builds
* OSX support and Xcode 5 project files

The vs2005 and vs2010 projects will contain relative paths that need to be updated if they remain in sub directories.  Linux and OSX demos now build statically linked images.