Style: Using the same writing style for `.sgcrc`

Currently we have two different writing styles in our `.sgcrc`

```json
  "lowercaseTypes": false,
  "initial-commit": {
    "isEnabled": true,
    "emoji": ":tada:",
    "message": "Initial commit"
  },
```

As you see we use camelcase (e.g. `lowercaseTypes`) and separating them with a `-` (e.g. `initial-commit`).

Maybe we should use camelcase for everything?