SOL005_#108 DELETE Method (on Individual threshold) description and response updated

src/SOL005/NSPerformanceManagement/NSPerformanceManagement.yaml

@@ -801,6 +801,9 @@ paths:
       summary: Delete a threshold.
       description: >
         This method allows to delete a threshold.
+        
+        As the result of successfully executing this method, the 
+        "Individual threshold" resource shall not exist any longer.
       parameters:
         - name: Accept
           description: >
@@ -814,7 +817,7 @@ paths:
           description: >
             204 NO CONTENT
 
-            The threshold was deleted successfully.
+            Shall be returned when the threshold has been deleted successfully.
             The response body shall be empty.
           headers:
             WWW-Authenticate: