Allow to pass a cdn data object in options

I think that the correct way to use google-cdn is not to store all the "cdn data" in lib/data.js.
Instead ppl should be able to create their own "cdn data" node modules and google-cdn should accept those in the options param. This will make the "cdn data" much more easily maintained and will also provide a very easy solution for ppl like me who would like to use their own company cdn for their apps.

Also, the name of this project needs to change :)