workaround SSL error if CA certs not provided

lib/httpLoader.js

@@ -1,6 +1,7 @@
 //
-// Basic schema loader that loads schemas over HTTP[S].
-// Wrapper for http.get.
+// Example schema loader that loads schemas over HTTP[S].
+// Wrapper for http.get. For SSL connections, the CA certificate is
+// not verified.
 //
 // If you were to write your own HTTP[S] loader, you’d probably want
 // to use https://github.com/mikeal/request to do the heavy lifting.
@@ -23,12 +24,15 @@ function loader(ref, callback, _depth) {
     return callback(err);
   }
 
-  var urlParts = url.parse(ref);
+  var options = url.parse(ref);
 
   var getter = http.get;
-  if (urlParts.protocol === 'https:') { getter = https.get; }
+  if (options.protocol === 'https:') {
+    options.rejectUnauthorized = false;
+    getter = https.get;
+  }
 
-  getter(ref, function(res) {
+  getter(options, function(res) {
 
     if (res.statusCode >= 300 && res.statusCode <= 399) {
       // redirect