Add note on Boots name: (#342)

## Description


Add a note on the repo used to be called Boots.

## Why is this needed



Fixes: #

## How Has This Been Tested?





## How are existing users impacted? What migration steps/scripts do we need?





## Checklist:

I have:

- [ ] updated the documentation and/or roadmap (if required)
- [ ] added unit or e2e tests
- [ ] provided instructions on how to upgrade

README.md

@@ -2,7 +2,7 @@
 
 [![Build Status](https://github.com/tinkerbell/smee/workflows/For%20each%20commit%20and%20PR/badge.svg)](https://github.com/tinkerbell/smee/actions?query=workflow%3A%22For+each+commit+and+PR%22+branch%3Amain)
 
-Smee is the network boot service in the [Tinkerbell stack](https://tinkerbell.org). It is comprised of the following services.
+Smee is the network boot service in the [Tinkerbell stack](https://tinkerbell.org), formerly known as `Boots`. It is comprised of the following services.
 
 - DHCP server
   - host reservations only