Document known issues, common RC2 errors, and workarounds

[natemcmaster]

Common errors

• Restore with out imports cref Mysterious Newtonsoft.Json conflict when depending on a library from a Web app NuGet/Home#2644 Need external dependencies to support .NET Standard in order to remove the requirement for imports in project.json  efcore#5176

Package Ix-Async 1.2.5 is not compatible with netcoreapp1.0 (.NETCoreApp,Version=v1.0). Package Ix-Async 1.2.5 supports:
      - net40 (.NETFramework,Version=v4.0)
      - net45 (.NETFramework,Version=v4.5)
      - portable-net45+win8+wp8 (.NETPortable,Version=v0.0,Profile=Profile78)
    Package Remotion.Linq 2.0.2 is not compatible with netcoreapp1.0 (.NETCoreApp,Version=v1.0). Package Remotion.Linq 2.0.2 supports:
      - net35 (.NETFramework,Version=v3.5)
      - net40 (.NETFramework,Version=v4.0)
      - net45 (.NETFramework,Version=v4.5)
      - portable-net45+win8+wp8+wpa81 (.NETPortable,Version=v0.0,Profile=Profile259)

• How to install tools cref CLI Commands: adding more descriptive error message to help with OOB experience efcore#5272
• dotnet-ef in powershell executes successfully but shows "Native command error" because of output to stderr "Done" message was shown when running dotnet ef migrations script efcore#5012
• This error

Cannot execute this command because 'Microsoft.EntityFrameworkCore.Tools' is not installed in project 'src\ConsoleApp1'. Add 'Microsoft.EntityFrameworkCore.Tools' to the 'tools' section in project.json.

Issues with a workaround

• Can't use CLI commands on a netstandard library. cref https://github.com/dotnet/cli/issues/2645
• Powershell 3 error

The expression after '&' in a pipeline element produced an object that was not valid. It must result in a command name, a script block, or a CommandInfo object.