Support multiple routes per API/service definition

[DonMartin76]

As an API developer, I would like to be able to fan out an API definition/service definition to multiple routes which in turn can have different settings, especially in terms of plugins.

This enables the following scenarios:

• Different rate limits for different parts of the API
• Fan-out to AWS Lambda/Azure Functions functions by route

Optional but nice to have:

• Enable routes which do not require authorization (no-auth), see also #96 ("Allow no-key access")

Things to consider:

• Update step (wicked.env: config-updater.js) to service/routes of the apis.json/config.json; the APIs still need a base route to enable Swagger UI
• Guidance in the Kickstarter for creating additional routes, good help texts describing how it has to be done
• Kong Adapter rearrangement for the synchronization
• Currently, auth settings are applied to the service(?); would need to be fanned out to the route definitions
• ...?

[DonMartin76]

This was implemented by @maksimlikharev and is merged for rc.12.