* Update dependencies from https://github.com/dotnet/arcade build 20190514.13
- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19264.13
* Update dependencies from https://github.com/dotnet/arcade build 20190516.2
- Microsoft.DotNet.Arcade.Sdk - 1.0.0-beta.19266.2
* Sweep attributes on GenericParameters and InterfaceImplementations
This fixes test failures that show up due to NullableAttribute with
recent versions of .NET Core (https://github.com/mono/linker/pull/570)
* Increase line count limit for reduced tracing test
* Add test for sweeping attributes on GenericParameters
These files are copied from https://github.com/dotnet/arcade.
They should usually not be updated manually, but will instead be updated
via automatic dependency flow mechanisms that create a PR in the repo.