Merge remote-tracking branch 'origin/rel/1.1.0-preview1' into dev

NuGet.config

@@ -3,8 +3,6 @@
   <packageSources>
     <clear />
     <add key="aspnetcore-tools" value="https://dotnet.myget.org/F/aspnetcore-tools/api/v3/index.json" />
-    <add key="dotnet-core" value="https://dotnet.myget.org/F/dotnet-core/api/v3/index.json" />
-    <add key="dotnet-tools" value="https://dotnet.myget.org/F/dotnet-buildtools/api/v3/index.json" />
     <add key="NuGet" value="https://api.nuget.org/v3/index.json" />
   </packageSources>
 </configuration>

build/build-quality.txt

@@ -1 +1 @@
-alpha1
+preview2