Add Visual Studio 2010 build for AppVeyor

appveyor.yml

@@ -108,6 +108,16 @@ environment:
       no_cgi: NO
       no_caching: NO
       configuration: Debug
+    - id: 10
+      compiler: msvc-16-seh
+      build_shared: NO
+      no_files: NO
+      enable_ipv6: YES
+      enable_ssl: YES
+      enable_websockets: YES
+      no_cgi: NO
+      no_caching: NO
+      configuration: Release
 
 install:
   # Derive some extra information