Fixed the Favorite() function for tweets. ID was being passed directly in the URL while Twitter requires it to be passed as a POST variable (inconsistent with how Retweet() works

Signed-off-by: aditya <dev@chimeracoder.net>
Run gofmt
adding support for appengine (must set urlfetch.Client through TwitterApi.HttpClient) should not affect not appengine operations.

Signed-off-by: aditya <dev@chimeracoder.net>