Docs overhaul (#1954)

Hugo is upgraded to a modern version, the reboot of the original theme is used, and links are replaced or removed. The readme is updated to state our utility in the first sentence. References to vGo and other old terminology has been moved to "modules" and more modern terminology.

README.md

@@ -10,7 +10,7 @@
 [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](http://makeapullrequest.com)
 [![Open Source Helpers](https://www.codetriage.com/gomods/athens/badges/users.svg)](https://www.codetriage.com/gomods/athens)
 
-Welcome to the Athens project! We are a proxy server for the [Go Modules download API](https://docs.gomods.io/intro/protocol/).
+Welcome to the Athens project! Athens is an open source, enterprise ready implementation of the [Go Module proxy](https://go.dev/ref/mod#module-proxy) for the [Go Modules download API](https://docs.gomods.io/intro/protocol/).
 
 See our documentation site [https://docs.gomods.io](https://docs.gomods.io) for more details on the project.
 
@@ -74,8 +74,7 @@ If you're not ready to contribute code yet, there are plenty of other great ways
 
 # Built on the Shoulders of Giants
 
-The Athens project would not be possible without the amazing projects it builds on. Please see
-[SHOULDERS.md](./SHOULDERS.md) to see a list of them.
+The Athens project would not be possible without the amazing projects it builds on. Please see [SHOULDERS.md](./SHOULDERS.md) to see a list of them.
 
 # Coding Guidelines
 
@@ -92,4 +91,5 @@ If you have concerns, notice a code of conduct violation, or otherwise would lik
 related to this code of conduct, please reach out `@arschles` on the [Gophers Slack](https://gophers.slack.com/).
 
 ---
+
 Athens banner attributed to Golda Manuel