public void Update(string guid, string username, string password)
        {
            var credentials = GetCredentialsForProfile(guid);

            if (credentials == null)
            {
                return;
            }

            credentials = new CredentialsObject(username, password);

            CredntialsObjects[guid] = credentials;
            Save();
        }
        public void Add(string guid, string username, string password)
        {
            var credentials = GetCredentialsForProfile(guid);

            if (credentials != null)
            {
                credentials             = new CredentialsObject(username, password);
                CredntialsObjects[guid] = credentials;
            }
            else
            {
                CredntialsObjects.Add(guid, new CredentialsObject(username, password));
            }

            Save();
        }