DDF-59, DDF-60, DDF-117: Added web service support for external web clients

Three changes which better enable the development of external web clients.
DDF-59 creates a geojson queryresponse transformer, allowing for a result set to be returned as an array of records in geojson metacard format
DDF-60 enables the client to request source availability information from DDF
DDF-117 enables the client to make JSON-P calls to the Rest endpoint and opensearch endpoint, allowing cross-domain queries