Bring the AlgorithmIdentifier.Parameters property back

Bring the AlgorithmIdentifier.Parameters property back

Add AlgorithmIdentifier.Parameters, but always set it to the empty array.

There aren't any really understood scenarios for why someone would want to read the algorithm parameters.  Combined with .NET Framework only assigning a non-empty value some of the time, never assigning the correct value, and not having a consistent incorrect value, the empty array seemed the best thing for now.

Commit migrated from https://github.com/dotnet/corefx/commit/64bab987f50b399b78cc1dc23a8e42325e5e175a