Provide SourceSystem and SourceName to request telemetry model

[stijnmoreels]

Is your feature request related to a problem? Please describe.
We should provide a SourceSystem and SourceName to the request telemetry when tracking requests, as they are required when distinguishing between HTTP requests and other types that needs to be tracked.

Describe the solution you'd like
Add a SourceSystem = "HTTP" and SourceName = method + uri property to the request telemetry model.
Make sure that it can be overwritten for other types but is fixed when tracking HTTP requests.

Additional context
https://github.com/arcus-azure/arcus-service-to-service-correlation-poc

[tomkerkhove]

Can you elaborate on this please? I'm not really sure what we are trying to achieve here?

[stijnmoreels]

Can you elaborate on this please? I'm not really sure what we are trying to achieve here?

We have to pass along an indication whether we're tracking HTTP requests or Azure Service Bus (or other types) requests. The SourceSystem was something you put in place to distinguish between the two. The SourceName is something that was also missing.

[tomkerkhove]

I don't recall that so I'm happy that you are here :p

[stijnmoreels]

Related to #250