add support of CA for superagent as and options object (not https.Agent instance). For some resons implementation in previous pull request #875, work only for first request, next ones don't use agent and fails with 403

Author: stanislav-polishchuk

README.md

@@ -299,6 +299,29 @@ var client = new SwaggerClient({
 });
 ```
 
+### Using custom http(s) agent
+In case if you need to sign all requests to petstore with custom certificate 
+
+```js
+var connectionAgent = {
+    rejectUnauthorized: false,
+    key: "/certs/example.key",
+    cert: "/certs/example.pem",
+    ca: ["/certs/example.ca.pem"]
+}
+
+var client = new SwaggerClient({
+  url: "http://petstore.swagger.io/v2/swagger.json",
+  connectionAgent: connectionAgent,
+  success: function() {
+    // upon connect, fetch a pet and set contents to element "mydata"
+    client.pet.getPetById({petId:1},{responseContentType: 'application/json'}, function(data) {
+      document.getElementById("mydata").innerHTML = JSON.stringify(data.obj);
+    });
+  }
+});
+```
+
 ### How does it work?
 The swagger javascript client reads the swagger api definition directly from the server.  As it does, it constructs a client based on the api definition, which means it is completely dynamic.  It even reads the api text descriptions (which are intended for humans!) and provides help if you need it:
 

lib/http.js

@@ -215,11 +215,12 @@ SuperagentHttpClient.prototype.execute = function (obj) {
     method = 'del';
   }
   var headers = obj.headers || {};
-  var r = request[method](obj.url);
 
   if (connectionAgent) {
-    r.agent(connectionAgent);
+      request = request.agent(connectionAgent);
   }
+
+  var r = request[method](obj.url);
 
   if (timeout) {
     r.timeout(timeout);