Updated broker to support legacy lab servers

Added new functions to the broker service (for both JSON and JSONP)

getLabList - Returns a list of lab identifiers
getLabStatus(id) - Returns the last status message for the lab
getEffectiveQueueLength(id) - Returns the effective queue length and
estimated wait time.

Updates to existing functions
getLabConfiguration(id) - Now takes a single lab id argument

I have updated the JSONP client to have a new interface
(HTML/Javascript/CSS only). It can communicate with the broker through
AJAX to display appropriate information on the page. The JSON client is
out of date.