refactor(perf): use webdriver to execute benchmarks

- use performance log of chromedriver / appium to get timeline data
  for calculating metrics for benchmarks
- change all benchmarks to be made of a standalone application
  and a protractor test that collectes timeline data
- fix and simplify benchmarks
- add dart2js to build
- remove benchpress

Closes #330

modules/benchmarks_external/test/perf/tree_perf.js

@@ -0,0 +1,18 @@
+"use strict";
+var util = require('../../../../tools/perf/util.js');
+
+describe('ng1.x tree benchmark', function () {
+
+  var URL = 'benchmarks_external/web/tree/tree_benchmark.html';
+
+  afterEach(util.verifyNoErrors);
+
+  it('should log the stats', function() {
+    util.runSimpleBenchmark({
+      url: URL,
+      buttons: ['#destroyDom', '#createDom'],
+      name: browser.params.lang+'.ng1.tree'
+    });
+  });
+
+});