Updated for node.js 0.11.x

* Implemented libuv for asynchonous tasks
* Added header file to attempt to be more like node.js programming structure
* Objects wrapped using node::ObjectWrap

Known issues ( _This is beta_ ):

* Memory leaks
* No way to select database version (default is 8.0)
* No easy way to compile for Windows
Merge branch 'master' of github.com:sugendran/node-freetds