Update ServiceStack.Plugins.ProtoBuf.csproj

changed nuget.targets to NuGet.targets
Update ServiceStack.Razor.csproj

changed nuget.targets to NuGet.targets
Update ServiceStack.WebHost.Endpoints.Tests.csproj

changed nuget.targets to NuGet.targets
Update ServiceStack.WebHost.IntegrationTests.csproj

changed nuget.targets to NuGet.targets
Merge pull request #815 from angelcolmenares/master

Fixed NuGet.target for linux