This should substantially improve the repeat-rendering time for pages
with large numbers of tweets since we don't need to go all the way to
twitter.com, which can take like a second, to render tweets properly.
To deploy this commit properly, one needs to run
./manage.py createcachetable third_party_api_results
(imported from commit 01b528e61f9dde2ee718bdec0490088907b6017e)
This allows us to handle the return_messages_immediately part of
get_updates requests without having to talk to the database.
(imported from commit ed0b7742d359efb21a0a4960f4fc25f4337e9ad4)
