UMIP 97 -Add SPACEXLAUNCH as a supported price identifier

The DVM should support price requests for SPACEXLAUNCH. The purpose of the SPACEXLAUNCH price identifier is to be a generalized way to evaluate the success rate of the rocket launches made by SpaceX before request date considering launches provided in ancillary data.

Ancillary data in the request will specify the parameters that should be considered during the oracle result determination process.