Add release notes for ML.NET 0.4 (dotnet#656)

Merge pull request dotnet#479 from shauheen/v0.3

Cherrypick to update release for V0.3

Update release notes link to use aka.ms. (dotnet#294) (dotnet#303)

Our release notes link is broken because the `Documentation` was renamed to `docs`. Fix this for the future to use a redirection link.

Add release notes for ML.NET 0.1 (dotnet#37)

* Add release notes for ML.NET 0.1

This closes issue dotnet#36