Provide .NETStandard compatible version

[musicm122]

Why:
Asp.net applications are moving toward .net core as a future standard. Moving this library to .net core would allow users to port their existing codebases to support the newer .net Standard.

What is involved:

• Replacing WebClient with HttpClient
• Convert Sync calls with proper Async equivalent versions
• Changing Refs from ApplicationException to Exception
• Adding\Changing Nuget Refs Such that the project can be used by .net core

[dmarlow]

I too would like to see this happen. This is just one of a long list of dependencies we have, but not having this would mean we'd be stuck until this was available.

[jakebanks]

+1 for this request please.

[mythjuha]

+1