Nuget Google.ProtocolBuffers 2.4.1.521 doesn't support win 8.1

[GoogleCodeExporter]

I am a class library developper and recently I just want to wrap the 
google.protocolbuffers and publish a class library to users.
But I encounter some problems:
I have already post a question on stackoverflow,with details such as some 
screenshots.
Link is here:
http://stackoverflow.com/questions/24670524/does-protobuf-csharp-port-support-wi
ndows-rt/24670946?noredirect=1#comment38286347_24670946

Original issue reported on code.google.com by fifa0...@gmail.com on 11 Jul 2014 at 6:48