Fix a little typo in the README

Author: bowsersenior

README.markdown

@@ -362,7 +362,7 @@ describe Twitter::API do
       it "returns a status by id" do
         status = Status.create!
         get "/api/v1/statuses/#{status.id}"
-        last_resonse.body.should == status.to_json
+        last_response.body.should == status.to_json
       end
     end
   end