Add delete commands to ManageUsersDisplay

Users/UsersManager.cs

@@ -79,6 +79,19 @@ namespace Akari.Provider.WaveshareUART.Users
             return false;
         }
 
+        public bool Remove(IEnumerable<User> users)
+        {
+            foreach (var user in users)
+            {
+                if (!Remove(user))
+                {
+                    return false;
+                }
+            }
+
+            return true;
+        }
+
         public bool Clear()
         {
             _users.Clear();