Add test for HttpClient (#62)

src-examples/ProxyInterfaceConsumer/Http/IHttpClient.cs

@@ -0,0 +1,14 @@
+namespace ProxyInterfaceConsumer.Http
+{
+    [ProxyInterfaceGenerator.Proxy(typeof(System.Net.Http.HttpClient, true))]
+    public partial interface IHttpClient : IHttpMessageInvoker
+    {
+        
+    }
+
+    [ProxyInterfaceGenerator.Proxy(typeof(System.Net.Http.HttpMessageInvoker))]
+    public partial interface IHttpMessageInvoker
+    {
+
+    }
+}