Update newer files after merge.

Author: ahsonkhan

src/ReportGenerator.Core.Test/MsBuildTest.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Diagnostics;
 using System.IO;
 using Xunit;

src/ReportGenerator.Core/Reporting/Builders/MhtmlReportBuilder.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Collections.Generic;
 using System.IO;
 using Palmmedia.ReportGenerator.Core.CodeAnalysis;