allow url, data, callback to be given in an object
remove param that wasnt being used
streamline the streaming xhr
new built versions
streamline very slightly more
update tests to new api
make tests a bit easier to develop by making support scripts run under supervisor
end-to-end integration tests for POST requests by echoing back what was received
can post an object and will be json-encoded
move responsibility for nulling data to oboe, sXHR is just a dumb wrapper on XHR