Save dropout scheduler step_num

Closes #203 (closed)

changed milestone to %DAN-P5: Improve training

added P2 label

assigned to @mboillet

added 2 commits

• b0bca1a7 - 1 commit from branch main
• 568e5880 - Save dropout scheduler step_num

Compare with previous version

I tested on Numen training, the dark curve is with the fix. The fix solves part of the problem.

I will take a look at the code to see if something else is not saved.

requested review from @yschneider

merged