Refactor this repo to better display information for each hub upgrade

[andynog]

Currently this repo has old information about previous chains. Doesn't show the information for the last hub. My suggestion is to revamp this repo with a structure that can accommodate both historical information for previous hubs and the current one. All of the upgrade share the same template and this would be really helpful for people to spin up nodes and join the hub.

One idea is to re-write the main README.md and explain the structure of the repo. Then have folders for each upgrage (e.g. cosmoshub-1, cosmoshub-3, etc). Then in each folder have a README with information specific to that upgrade. We could also hyperlink the historical archives hub data on each one (e.g. https://archive.interchain.io/hub1.html)