document the deployment procedure please please please

We need tod ocument the deployment procudere because:

1. Every second deployment fails because of some human error
2. Only oren really knows how it works

So we need step-by-step documentation on:

- how to add a new dao to an existing subgraph version
- how to deploy a new subraph version

These steps involve:

- copy an exiting directory or git checkout (?)
- edit docker-compose and assign new ports
- star the dcker cotnainers
- editing the necessary files for subgraph deploymnet
- npm run deploy
- check if server is done indexing
- configure nginx and reload it

We can document this in the https://github.com/daostack/devops/ repo so it will not be public.

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the procedure is quite complex, perhaps more than necessary.

My impression is that deployment (of a new rinkeby or mainnet subgraph version) has become very cmplex, with file changes (apparently) in these files that influence the results:

* the `.env` file
* the `daos/` directory
* the `ops/mappings.json`
* the `ops/mapping.json` container
* the migration.json from `daostack/migration`
* the docker-compose file

If that is really the case, perhaps it is also a good idea to reorganize this

Start by tracing the deployment procedure in the devops repository and reviewing the named .env file, daos/ directory, ops/mappings.json, ops/mapping.json container, migration.json, and docker-compose file. Document adding a DAO, deploying a subgraph version, running npm run deploy, checking indexing, and configuring nginx; done means a newcomer can follow and verify the full procedure.

Written by the indexing model from the issue text.