Added params to fql query method

Hello!

First of all, thank you for this library, it's incredibly easy to use and very helpful.

I'm writing an application which requires an access token to be provided per-request for FQL queries, which I noticed your application does not support, since appending it to the query string makes the ampersand get eaten by the `encodeURIComponent` method. Since the FQL method simply calls the get method, I realized adding this support would not be complicated, so I went ahead and added it in my fork (so I myself could use it). This makes the FQL method signature closer to the get method signature, but I did add in a check to make sure the modifications are backwards compatible. In the event this is useful for you, I have opened this pull request.

Thanks!