Replace README with link to obol-docs

[xenowits]

🎯 Problem to be solved

The current README is not regularly updated and contains some outdated stuff as well. It is also mostly duplicate of the quickstart-alone guide in our docs - https://docs.obol.tech/docs/int/quickstart/quickstart-alone.

So, instead of maintaining two separate guides, let's have only one. This is also consistent with the README of the CDVN repo, where we link directly to obol docs.

🛠️ Proposed solution

Replace README with the following text:

![Obol Logo](https://obol.tech/obolnetwork.png)

<h1 align="center">Distributed Validator Cluster with Docker Compose</h1>

This repo contains a [charon](https://github.com/ObolNetwork/charon) distributed validator cluster which you can run using [docker-compose](https://docs.docker.com/compose/).

This repo aims to give users a feel for what a [Distributed Validator Cluster](https://docs.obol.tech/docs/int/key-concepts#distributed-validator-cluster) means in practice, and what the future of high-availability, fault-tolerant proof of stake validating deployments will look like.

A distributed validator cluster is a docker-compose file with the following containers running:

- Single [Nethermind](https://github.com/NethermindEth/nethermind) execution layer client
- Single [Lighthouse](https://github.com/sigp/lighthouse) consensus layer client
- Six [charon](https://github.com/ObolNetwork/charon) Distributed Validator clients
- Two [Lighthouse](https://github.com/sigp/lighthouse) Validator clients
- Two [Teku](https://github.com/ConsenSys/teku) Validator Clients
- Two [Nimbus](https://github.com/status-im/nimbus-eth2) Validator Clients
- Prometheus, Grafana and Jaeger clients for monitoring this cluster.

![Distributed Validator Cluster](DVCluster.png)

In the future, this repo aims to contain compose files for every possible Execution, Beacon, and Validator client combinations that is possible with DVT.

# Quickstart

Check the Obol [docs](https://docs.obol.tech/docs/int/quickstart) for detailed instructions on how to get started using this repo.

# Project Status

It is still early days for the Obol Network and everything is under active development.
It is NOT ready for mainnet.
Keep checking in for updates, [here](https://dvt.obol.tech/) is the latest on charon's supported clients and duties.

# FAQs

Check the Obol docs for frequent [errors and resolutions](https://docs.obol.tech/docs/int/faq/errors)