[Feature Request] Project templates should have an option to generate the "call an API" part

[jmprieur]

Is your feature request related to a problem? Please describe.
The project templates show how to create a Web app, or a Web api, but they don't show how to introduce the second part: call a downstream API.

Describe the solution you'd like
Have 2 more mandator parameters and one optional parameter to the templates:

• calledApi: URL to the API (for instance http://graph.microsoft.com/v1.0/me)
• calledApiScopes: Scopes requested to call the web API
• tokenCacheImplementation: [optional] InMemory, Redis, Sql => to generate the right cache

If these parameters are present:

• the Startup.cs file adds the CallWebApis part and a token cache.

Describe alternatives you've considered
None

[jennyf19]

Included in 0.2.0-preview release