fix(build): switch to cjs output for es5.

System output does not work at the current versions of TS and
system.js. Will revisit after upgrading TS.

Removes unused traceur tooling.

Closes #3974

docs/docs-package/index.js

@@ -1,5 +1,3 @@
-require('../../tools/transpiler/index.js').init();
-
 var Package = require('dgeni').Package;
 var jsdocPackage = require('dgeni-packages/jsdoc');
 var nunjucksPackage = require('dgeni-packages/nunjucks');