Add poem lines

Branched from passport-authentication

It should be possible to merge this branch in before or after the poem-security branch (https://github.com/jimguys/poemlab/pull/14). The intention is for these two branches to be independent of each other. It might make sense to do this feature first, so we can access all poems. 

This feature gives us the ability to actually write poems that will be saved to the database. Poem lines are sent to the server, saved to the database, and broadcast out to all connected clients. 

jQuery is now responsible for escaping html entities for new lines, and the jade template will escape html entities for existing lines.