Redirect the old documentation to the new one

[kpko]

Hi,

it seems like the a few dead links are already fixed at https://docs.microsoft.com/en-us/dotnet/orleans/streaming/stream-providers but not at https://dotnet.github.io/orleans/docs/streaming/stream_providers.html. I'm new to Orleans and the first documentation I found googling was the second, non-functional link.

Are these two documentations somehow kept in sync?

If not, should the "old" documentation at dotnet.github.com/orleans/ not redirect to the new documentation at docs.microsoft.com?

I've created a pull request to fix the links (#65) before I've discovered the hint at https://github.com/dotnet/orleans-docs.