Update image list (#688)
Update image list (#688)

* Update image list

Remove Nano Exclusion (now just covered by Helix)
Disable Win10, which is a non-functional 2016 TP5 image
tannergooding/dotnet-ci,dotnet/dotnet-ci,mmitche/dotnet-ci,tannergooding/dotnet-ci,mmitche/dotnet-ci,dotnet/dotnet-ci