Update README with vs15.3 information (#2186)
Update README with vs15.3 information (#2186)

Also fixed a link to the rolling job from Desktop to Full, since we
changed the name of the job.
cdmihai/msbuild,cdmihai/msbuild,chipitsine/msbuild,chipitsine/msbuild,cdmihai/msbuild,Microsoft/msbuild,AndyGerlicher/msbuild,mono/msbuild,chipitsine/msbuild,jeffkl/msbuild,sean-gilliam/msbuild,sean-gilliam/msbuild,chipitsine/msbuild,AndyGerlicher/msbuild,mono/msbuild,Microsoft/msbuild,cdmihai/msbuild,sean-gilliam/msbuild,AndyGerlicher/msbuild,rainersigwald/msbuild,mono/msbuild,sean-gilliam/msbuild,rainersigwald/msbuild,jeffkl/msbuild,jeffkl/msbuild,AndyGerlicher/msbuild,rainersigwald/msbuild,rainersigwald/msbuild,mono/msbuild,Microsoft/msbuild,Microsoft/msbuild,jeffkl/msbuild