Merge pull request #111 from carlossanlop/AnonymousPipeServerStreamAcl

Add AnonymousPipeServerStream method that takes an ACL

The original corefx PR was already signed off, but the CI did not finish on time before the 5pm deadline: dotnet/corefx#42392

Approved API proposal: dotnet/corefx#41657

We don't currently have a way to create a pipe with a given ACL in .NET Core. We can modify the ACL, but it would be more secure to have the proper ACL on the pipe from the start.

This PR adds a new static class and method that can create an AnonymousPipeServerStream taking a PipeSecurity object, reusing code that can already perform this task.