Closes#76.
Note I had not yet manage to successfully test this.
Manually trying the parameterized NixOps4 I tried using the following
command, tho I had yet to get this to work as well:
```sh
DEPLOYMENT='{"domain": "fediversity.net", "mastodon": {"enable": false},
"pixelfed": {"enable": true}, "peertube": {"enable": false}}' nix
develop --extra-experimental-features "configurable-impure-env"
--command nixops4 apply test
```
(or rather, I used a hardcoded Nix here so as to make it not use Lix.)
So far this had failed for me with:
```
the following units failed:
acme-mastodon.web.garage.fediversity.net.service
...
nixops4 error: Failed to create resource garage-configuration
```