Improve connectors' post-out capabilities

[smurthas]

it's straight forward to add. we should be able to post to twitter and fb at a minimum, bonus == tumblr. as noted in #887, wordpress as well (probably should be done as part of that issue, but mentioning it here for coordination purposes)

[temas]

Look at the twitter code for a current thought on how this could be implemented. It currently has the ability to post tweets.