we should move the repository directory inside a network directory

I try to run

```
➜ ~ coffee --network testnet remote add folgore-git https://github.com/coffee-tools/folgore.git
✓ Remote added!
➜ ~ coffee remote add folgore-git https://github.com/coffee-tools/folgore.git
✗ Fetch remote from https://github.com/coffee-tools/folgore.git error: Error while add remote: code: 1, msg: repository with name: folgore-git already exists
✗ Error: code: 1, msg: repository with name: folgore-git already exists
```

This must not happen, because for each network we can add a different remote (e.g: a fork for testnet) so we should move the `repository` inside the `network` subdirectory