corrected the Deferred defn. for gdocs.js

The existing definition of `Deferred` is causing uncaught errors with _.isUndefined (when used in async mode with other frameworks).

Other recline backends (like csv etc., including the main recline.js) that did not have this problem are using this `typeof jQuery !== undefined` definition.

Correcting the code to be compatible with other backends and also eliminate the uncaught error with async exec.