Document common integrations' basics

[peter-csala]

Hi folks,

Here at the discussions space and on StackOverflow I can see recently a recurring theme "how to integrate Polly with XYZ?" These integrations are varying from HttpClient, RestSharp through FluentResult, OneOf till Entity Framework Core, grpc.net...

What do you guys would it make sense to have a dedicated common integrations section on pollydocs where we demonstrate some basic use cases?

cc: @martincostello , @martintmk

[martincostello]

Sounds reasonable to me, though I would just link off to other docs (e.g. in the HttpClient case for HttpClientFactory and the new resilience libraries) if there's existing content rather than creating our own.