message: Support for skipSelenium and seleniumPort. Fixes Polymer/web-component-tester#110
diff: * Code distributed by Google as part of the polymer project is also
  * subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
  */
  +var chalk = require('chalk');
  +
  var browsers = require('./browsers');
  var selenium = require('./selenium');
  @@ -56,6 +58,15 @@ module.exports = function(wct, pluginOptions) {
  wct.hook('prepare', function(done) {
  if (!eachCapabilities.length) return done();
  + // Already have your own Selenium server running?
  + if (pluginOptions.skipSelenium) {
  + if (!pluginOptions.seleniumPort) {
  + return done('When skipSelenium is true, you must specify a port via seleniumPort or SELENIUM_PORT');
  + }
  + wct.emit('log:info', 'Using user-managed Selenium server on port', chalk.yellow(pluginOptions.seleniumPort));
  + return done();
  + }
  +
  wct.emitHook('prepare:selenium', function(error) {
  if (error) return done(error);
  // Is Selenium already running on a specified port?
  