Add checkpointing documentation page or section

[b-reyes]

It is often the case that checkpointing can be beneficial for long running workflows. We currently do not have any documentation on checkpointing. If possible, we should add a section or page about checkpointing.

[b-reyes]

Items should also be included that explain how certain jobs can be restarted from the last point. For example, when training a network, you can save the network state at certain intervals and then load that network from that state later on.

[mohalkh5]

This is a great idea and definitely something that would be valuable to include.
One thought is that checkpointing can get fairly broad depending on how deep we want to go. If we are aiming for a more detailed and comprehensive treatment, this could become quite extensive.
If that is the case, it might make sense to consider breaking this out into a separate story.