Add documentation on how to use the tools in this repo

[manodeep]

Currently there is no usage documentation, and the only examples would be what we have already done in the access-models-scaling repo. Would be best if we added some documentation, ideally with two different use-cases - i) end-users, and ii) developers.

[manodeep]

The usage docs came up because I wanted to check how to add an experiment directory into the experiment list within the profiling manager.