This pull request adds a report on the major bandwidth usage within Tendermint.
[Rendered](https://github.com/tendermint/tendermint/blob/wb/p2p-rfc/docs/rfc/rfc-027-p2p-message-bandwidth-report.md)
#### PR checklist
- [ ] Tests written/updated, or no tests needed
- [ ] `CHANGELOG_PENDING.md` updated, or no changelog entry needed
- [ ] Updated relevant documentation (`docs/`) and code comments, or no
documentation updates needed
* docs/rfc: add testnet RFC
Following several discussions internal to the Tendermint engineering
team, I am posting an RFC discussing the high-level details of the
Tendermint team owning and operating a long-lived testnet in order to
build experience running Tendermint, and to demonstrate that Tendermint
is stable under production workloads.
The outcome of this RFC will be a new track of work to begin building
and maintaining a testnet associated with the main branch of tendermint.
See the "Testnet MVP" section specifically for some of the first
milestones.
Note, I added the RFC where it would live once #9115 is merged to
restore the RFC layout from the v0.36.x branch. docs/rfc/README.md will
need to be updated to include this RFC once #9115 is merged.
This RFC is related to #9078.
* docs/rfc: minor updates to testnet rfc
* docs/rfc: respond to more feedback on testnet RFC
* docs/rfc: add RFC 023 to rfc index
