Add remove method for local storage models

Author: laffra

ltk/widgets.py

@@ -494,6 +494,10 @@ def changed(self, name, value):
         """ Called when an attribute of the model has changed """
         if hasattr(self, "_key"):
             self.__store.setItem(self._key, self.encode())
+    
+    def remove(self):
+        """ Remove the model from local storage """
+        self.__store.removeItem(self._key)
 
     @classmethod
     def load(cls):