create new sessions as required
more work
improve behavior of test requests based on testing with sharejs
require sinatra/base instead of sinatra

* to stop polluting the top namespace
avoid an exception for now
POST requests are handled seperately to GETs
404 POST requests for now
disable rack-protection
handle the first channel POST from the client

* the first POST
  * accepts the first message from the client
  * returns a data array with info on the new session that has been
    established
* subsequent POSTs return a bookeeping reponse on the state of the
  session