update SAMSHub.app to still return SAMSApp Object instead of a dict

by changing addApp it is necessary to change this method according to
the new _appList and _apps structure

sams_classes/sams_hub.py

@@ -51,7 +51,7 @@ class SAMSHub:
   
   def app(self, name):
     try:
-      return self._apps[name]
+      return self._apps[name]['app']
     except:
       raise AppNotExist