Support fully custom network cost and type population

[bliptec]

trafficstars

Similar to how different HTTP clients can be used, it would be valuable to be able to replace the default population logic for network cost and network type for clients that want to use their own networking logic

This would be additionally useful due to:

• The current network type logic uses a deprecated, potentially buggy, wininet call #282
• The network cost detection currently spins up its own thread just to receive network cost info

[maxgolov]

I want to mention that I added a sample how the fields can be populated via Semantic Context API. Technically if PAL logic that obtains these values is commented out / not compiled-in, then it's still possible for a customer app to populate the fields using Semantic Context. Example in PR #303 .. Basically then the custom logic you're asking for would have to live somewhere in your app, in that spot where you obtain the ILogger.