Correct reloading

modify script to correct reloading with scheduler change: it allows to change the lr scheduler parameters after a reload of checkpoint (before everything was dropped and return to the initial checkpoint state). Of course, special care is needed if the reload is at the point of a LR decay.

alsop added more parameters info in the log to check current scheduler state

a bit hacky, so I added a parameter in the json (stage3.json) to use it or not

Note: this is needed for people already started the stage 3 with the old parameters