*   Normalization can now accept mean and variance values as init args.
*   In `Attention` and `AdditiveAttention` layers, the `call()` method now
    accepts a `return_attention_scores` argument. When set to True, the layer
    returns the attention scores as an additional output argument.
*   Adds `tf.metrics.log_cosh` and `tf.metrics.logcosh` API entrypoints with the
    same implementation as their `tf.losses` equivalent.

	if !sys.Initialized() {
		return errServerNotInitialized
	}

	return sys.store.UserNotificationHandler(ctx, accessKey, svcUser)
}

// initStore initializes IAM stores
func (sys *IAMSys) initStore(objAPI ObjectLayer, etcdClient *etcd.Client) {
	if sys.LDAPConfig.Enabled() {
		sys.SetUsersSysType(LDAPUsersSysType)
	}

	if etcdClient == nil {