Unit tests for routes functionality

* Fixed a bug in lib/config.js how it creates absolute paths to resources defined in routes.
* Added onStart callback in lib/executor.js.  This is needed because unit tests need to know when the express has actually started before running tests.
* Unit tests for routes functionality config.js added to config.spec.js
* Unit tests for routes functionality in executor.js added to new file: executor.http.spec.js