'Call all registered callbacks\' on_epoch_end functions.
Arguments:
epoch (int): index of epoch that is ending'

def on_epoch_end(self, epoch):

    for c in self.callbacks:
        if c.should_fire(self.callback_data, self.model(), epoch, c.epoch_freq):
            c.on_epoch_end(self.callback_data, self.model(), epoch)
    self.epoch_marker += self.epoch_minibatches
    self.callback_data['time_markers/minibatch'][epoch] = self.epoch_marker
    self.callback_data['time_markers'].attrs['epochs_complete'] = (epoch + 1)
    self.callback_data['time_markers'].attrs['minibatches_complete'] = self.epoch_marker
    self.callback_data.flush()
