Timer callback

[lvoegtlin]

Is your feature request related to a problem? Please describe. Extend the Timer callback to be able to log the after every training epoch the time and also log the end running time of the fit and the evaluate stages.

Describe the solution you'd like Inherit from the original callback and just add the logging functionality on the main thread to make it log on the default loggers.

Checklist

• [x] Add logging functionality
• [x] Add epoch vise time capturing and logging
• [x] Config
• [x] Test
• [x] PR

[lvoegtlin]

The original callback if for fixing the run time of the experiment and not track the elapsed time. We have to create our own custom callback