remove /langversion from web.config

Author: Jinhuafei

src/Packages/Microsoft.CodeDom.Providers.DotNetCompilerPlatform/Microsoft.CodeDom.Providers.DotNetCompilerPlatform.nuproj

@@ -23,9 +23,6 @@
         <NuGetContent Include="Content\net45\*">
             <Destination>content\net45</Destination>
         </NuGetContent>
-        <NuGetContent Include="Content\net46\*">
-            <Destination>content\net46</Destination>
-        </NuGetContent>
         <NuGetContent Include="build\*">
             <Destination>build\net45</Destination>
         </NuGetContent>

src/Packages/Microsoft.CodeDom.Providers.DotNetCompilerPlatform/content/net45/web.config.install.xdt

@@ -28,7 +28,7 @@
         extension=".cs"
         type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
         warningLevel="4"
-        compilerOptions="/langversion:6 /nowarn:1659;1699;1701"
+        compilerOptions="/nowarn:1659;1699;1701"
         xdt:Transform="Insert" />
     </compilers>
   </system.codedom>
@@ -51,7 +51,7 @@
         extension=".vb"
         type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.4.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"
         warningLevel="4"
-        compilerOptions="/langversion:14 /nowarn:41008 /define:_MYTYPE=\&quot;Web\&quot; /optionInfer+"
+        compilerOptions="/nowarn:41008 /define:_MYTYPE=\&quot;Web\&quot; /optionInfer+"
         xdt:Transform="Insert" />
     </compilers>
   </system.codedom>