Protocol Docs in single repo

[st3b1t]

I think it is a sensible idea to separate protocol specification documentation from this repository that accept PR also from any(exotics) projects/coin, one list some good reasons for this:

1. the protocol should be implementation agnostic
2. the documentation that exists along with the code might have been fine in the early days of the project
3. there may be new protocol specifications that electrumx may never be able to implement(the project seems to me to be inactive compared to others)
4. a dedicated repository would give greater visibility and dignity to the protocol specification
5. it would be easier to manage PR and protocol-specific ideas that have little to do with the specific implementation
6. it would all make more sense and clear in the eyes of new contributors