Add time spent on each epoch

It would be helpful to show how much time it took on each epoch like this:

accuracy | loss | epoch | train | time
-- | -- | -- | -- | --
0.817 | 0.722 | 0 | True | 00:21
0.850 | 0.547 | 0 | False | 00:01
0.894 | 0.392 | 1 | True | 00:21
0.862 | 0.462 | 1 | False | 00:01
0.918 | 0.272 | 2 | True | 00:22
0.896 | 0.318 | 2 | False | 00:02
0.938 | 0.205 | 3 | True | 00:22
0.924 | 0.252 | 3 | False | 00:02
0.958 | 0.151 | 4 | True | 00:23
0.929 | 0.230 | 4 | False | 00:03

I would be happy to add this feature.