ensure we have a bigint id

spec/models/twitter_user_info_spec.rb

@@ -0,0 +1,10 @@
+require 'spec_helper'
+
+describe TwitterUserInfo do
+  it "does not overflow" do
+    id =  22019458041
+    info = TwitterUserInfo.create!(user_id: -1, screen_name: 'sam', twitter_user_id: id)
+    info.reload
+    info.twitter_user_id.should == id
+  end
+end