Initialization of "launch_data" is the only way to set xapi mandatory info

[jono-poltrack]

Right now, the adlcp:dataFromLMS element is the only way to create the json object used to initialize the values needed for an xAPI statement (lrs info, activity id, scorm version, etc).

Need to keep this, but allow the user to choose to NOT use dataFromLMS and instead set these values on their own.