Allow for third-party Xbox 360 controllers

node-xbox-controller finds controllers by their name in the HID devices, but
needs to be informed about third-party controllers that don't necessarily label
themselves as 'controller' (as the official 360 controller does).

Users can now specify a string for node-xbox-controller to use when attempting
to hook up to a controller by specifying their connection like this:

    Cylon.robot
      connection:
        name: "controller"
        adaptor: "joystick"
        controller: "xbox360"
        type: "afterglow" # <= tells node-xbox-controller what to look for
Merge pull request #4 from hybridgroup/custom-360-controllers

Allow for third-party Xbox 360 controllers