.net core unsupported package 'System.Net.Http.Formatting.Extension'

[msx752]

there is no alternative for NETStandard.Library (CoreBot.Logic, CoreBot.RocketAPI)
so project won't be convertable so far until find a solution.

(error occur while package installing)

[msx752]

sample source code of System.Net.Http.Formatting.Extension http://aspnetwebstack.codeplex.com/SourceControl/latest#src/System.Net.Http.Formatting/