Merge pull request #2930 from eerhardt/MvcNet46

dotnet build raises errors MVC apps target net46.

TestAssets/TestProjects/AppWithNet46AndRoslyn/.noautobuild

@@ -0,0 +1 @@
+noautobuild

TestAssets/TestProjects/AppWithNet46AndRoslyn/Program.cs

@@ -0,0 +1,10 @@
+namespace AppWithNet46AndRoslyn
+{
+    public class MyApp
+    {
+        public static void Main()
+        {
+            System.Console.WriteLine("Hello, World!");
+        }
+    }
+}

TestAssets/TestProjects/AppWithNet46AndRoslyn/project.json

@@ -0,0 +1,11 @@
+{
+  "buildOptions": {
+    "emitEntryPoint": true
+  },
+  "dependencies": {
+    "Microsoft.CodeAnalysis.CSharp": "1.3.0-beta1-20160429-01"
+  },
+  "frameworks": {
+    "net46": { }
+  }
+}