chore: 2.1.1 version

chore(common): update to official .net core, 2.1.0, and remove mentio…

…ns of VS Preview

docs(common): improve getting started, update version

docs(grid): improve overview snippet

chore(common): update version

chore(api): fix improve link issue

docs(common): update version

chore(common): update js interop file version

docs(common): static asset requirements and issues