fix incorrect variable replacement for messageSubject in featureSelector;add checkHandler and checkSubject to LiveMessagesUtil class and run argument not null checks in LiveMessagesUtil;Signed-off-by: Stefan Maute <stefan.maute@bosch.io>
add argumentNotNull check for type to registerForMessages implementations in LiveFeatureHandleImpl, LiveImpl and LiveThingHandleImpl;Signed-off-by: Stefan Maute <stefan.maute@bosch.io>