[Feature Request] Application Insights Application Map Support

Since Application Insights is now the "de facto" monitoring platform for Azure Functions, one of the most incredibly useful features is the [Application Map.
](https://docs.microsoft.com/en-us/azure/azure-monitor/app/app-map)

However, all of my Azure Functions all show up under a single application currently, so it's basically an opaque single function. I want my application map to look like this with all of the queues connecting the different functions and whatnot.

Is it possible to:
1. Expose the iLogger Interface to powershell as an object via a cmdlet https://github.com/Azure/azure-functions-host/wiki/ILogger for custom logging
1. Expose the Application Insights telemetry client to a variable to allow for additional logging and correlation. I guess one could create a new telemetry client using the invocation information from environment variables, but this requires a lot of explicit knowledge vs. knowledge the worker already implicitly has.
1. When logging, set the CloudRole to the Azure Function Host name and the CloudRoleInstance to the individual function name. Here's the telemetryinitializer API for some of that.
https://docs.microsoft.com/en-us/azure/azure-monitor/app/api-filtering-sampling#add-properties-itelemetryinitializer