add legacy script

MediaBrowser.WebDashboard/MediaBrowser.WebDashboard.csproj

@@ -272,6 +272,9 @@
     <Content Include="dashboard-ui\legacy\objectassign.js">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>
+    <Content Include="dashboard-ui\legacy\selectmenu.js">
+      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+    </Content>
     <Content Include="dashboard-ui\livetvguideprovider.html">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
     </Content>