update addApp in sams_app.py to pass test_Sams_hub.py and fix #29

sams_classes/sams_hub.py

@@ -30,7 +30,7 @@ class SAMSHub:
     self._flaskApp.context_processor(self._context_processor)
     self._flaskApp.secret_key = 'my awesome SAMSHub secret_key'
   
-  def addApp(self, app: SAMSApp = None):
+  def addApp(self, app: SAMSApp = None, alias = None):
     if not isinstance(app, SAMSApp):
       raise TypeError('Argument app has to be a SAMSApp.')
     self._apps[app.name] = app
@@ -38,7 +38,7 @@ class SAMSHub:
     if app.name == self._config.get('main_app'):
       self._flaskApp.register_blueprint(app.blueprint)
     self._flaskApp.register_blueprint(
-      app.blueprint, url_prefix = '/' + app.name)
+      app.blueprint, url_prefix = '/' + (alias or app.name))
   
   @property
   def appKeys(self):