[fix] properly support iojs with test checking for HTTPS

Author: jcrugzz

test/lib-https-proxy-test.js

@@ -1,4 +1,5 @@
 var httpProxy = require('../lib/http-proxy'),
+    semver    = require('semver'),
     expect    = require('expect.js'),
     http      = require('http')
     https     = require('https'),
@@ -166,7 +167,7 @@ describe('lib/http-proxy.js', function() {
 
         proxy.on('error', function (err, req, res) {
           expect(err).to.be.an(Error);
-          if (process.versions.node.indexOf('0.12.') == 0) {
+          if (semver.gt(process.versions.node, '0.12.0')) {
             expect(err.toString()).to.be('Error: self signed certificate')
           } else {
             expect(err.toString()).to.be('Error: DEPTH_ZERO_SELF_SIGNED_CERT')