replaced env.get call with the optional docsHomeBaseUrl value
added buddy-to-access support to data updates checks
finally getting rid of this absurd way of globally accessing the current guest's info
global guest info is now in App.buddyToAccess
make sure we refresh the app's state after we got hold of the new buddyToAccess
use buddyToAccess instead of the antiquated App.getUID() to retrieve the guest whose data we are looking at
added a reload method to force reloading of the sources json and calling the init function again
detect a change of the guest whose data we're looking at and force a grapher reload when that happens