[VS Addin] Add visual studio 2012 support

visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs

Index: visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs
diff --git a/visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs b/visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs
index c15bcb8dc6e81cbee9d96653afa2163ae13456e9..e52a0b43ff17e587fdb082d29891d8bf4107817e 100644
--- a/visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs
+++ b/visual_studio/NativeClientVSAddIn/UnitTests/CompileParallelTest.cs
@@ -19,7 +19,7 @@ namespace UnitTests
         private static string SolutionBaseName_ = "CompileParallelTest";
 
         [ClassInitialize]
-        public new static void ClassSetUp(TestContext testContext)
+        public static void ClassSetUp(TestContext testContext)
         {
             BaseCompileTest.ClassSetUp(testContext, SolutionBaseName_);
         }
@@ -45,7 +45,6 @@ namespace UnitTests
 
             // Add property sheet that enables multiprocessing
             VCConfiguration config;
-            IVCRulePropertyStorage rule;
             config = TestUtilities.GetVCConfiguration(project, "Debug", platform);
             config.AddPropertySheet("multiprocess.props");
             config = TestUtilities.GetVCConfiguration(project, "Release", platform);