Better UI information during training

[Connor-Bowley]

It would be nice if during the training we got other info in addition to the progress bar. Something like what the current accuracy (or other applicable statistic) is.

[mturja-vf-ic-bd]

These statistics (accuracy, auc etc) are shown in tensorboard which the user can see using show_log button. However, right now, the user has to start the tensorboard server outside of the application which is not ideal.