Possible issues with max_iters when loading/saving engine's state

[vfdev-5]

Currently Engine implicitly assumes : https://github.com/pytorch/ignite/blob/e3ef192c94d0d793a9303bec915fb846aaa3161f/ignite/engine/engine.py#L122

but we recently introduced possibility to trigger a run with max_iters. If epoch length is unknown, saving and reloading engine's state probably wont work. We have to ensure that everything still works as expected.

@thescripted would you be interested in looking into this ?

[thescripted]

Yeah definitely, will check it out

[vfdev-5]

Thanks @thescripted !

[vfdev-5]

@thescripted could you please advance on this issue and have any updates ?