Accurate error propagation from RoGetActivationFactory (microsoft#559)

Harden operator wstring_view (microsoft#546)

Fix holes in IObservableVector<IInspectable> (microsoft#544)

Update README.md

Revert "Remove use of umbrella libraries (microsoft#520)" (microsoft#529

)

Fix async for testwinrt (microsoft#515)

Support for x86 builds with Clang (microsoft#511)

Fix regression in Xaml apps (microsoft#485)

Provide winrt_activation_handler to hook/mock activation (microsoft#477)

Revert "Revert "Build tweaks to simplify Win7 smoke testing (microsof…

…t#471)""

This reverts commit 5579f5d.