Define a required parameter using a sugar API

Dieses Issue hat noch niemand übernommen.

At the moment, it is not possible to use `@param` shortcuts like `@param.query.string` to define a required parameter.

One has to use `@param` directly (but don't have to specify the type since LB4 can infer the type from TypeScript metadata). For example:

```ts
@param({name: 'format', in: 'query', required: true}) format?: string
```

Ideally, I would like LB4 to provide the following syntax for annotating parameters as required:

```ts
@param.query.string('format', {required: true}) format?: string
```

## Acceptance criteria

- [ ] Modify all `@param.SOURCE.TYPE()` shortcuts (and possibly other similar shortucts) to accept a new optional argument of type `Partial` and use the provided properties to enhance (or amend) the spec generated by the decorator.
- [ ] Modify `@param.array()` in a similar way, the new optional argument will be the fourth arg.
- [ ] Modify `@param.query.object()` similarly, the new optional argument will be the third arg.
- [ ] Verify that the API documentation is able to pick up the changes

---

## 🎆 Hacktoberfest 2020

Greetings :wave: to all Hacktoberfest 2020 participants!

Here are few tips 👀 to make your start easier, see also #6456:

- Before you start working on this issue, please leave a comment to let others know.
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Beginne damit, die TypeScript-Implementierungen der Shortcuts @param.SOURCE.TYPE(), @param.array() und @param.query.object() zu finden, und untersuche anschließend, wie deren generierte ParameterObject-Spezifikationen für die API-Dokumentation bereitgestellt werden. Aktualisiere die Shortcuts so, dass sie die genannten optionalen Eigenschaften akzeptieren, und überprüfe, dass die Dokumentation sie einschließlich erforderlicher Parameter widerspiegelt.

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