Adding node.js bindings

Added the GYP build system as this is a requirement for native modules in Node.

https://github.com/TooTallNate/node-gyp
https://code.google.com/p/gyp/wiki/GypUserDocumentation

This work could be used to replace the CMake bits, as well as the Visual Studio and XCode projects. This should make keeping up with the bindings easier. If you'd like additional work there its no problem.

Then bindings were created between Node and the interface exposed.

http://nodejs.org/api/addons.html