Add NodeError, fixup stack

The stack includes the error message as its first line. Making the message different than the first line of the stack can cause issues with tools that expect them to be consistent.

For example, Intern currently displays this error when it can't connect to Selenium:

```
Error: [POST http://localhost:4444/wd/hub/session] connect ECONNREFUSED
Error: connect ECONNREFUSED
  at errnoException  <net.js:904:11>
  at Object.afterConnect [as oncomplete]  <net.js:895:19>
```

It should be displaying:

```
Error: [POST http://localhost:4444/wd/hub/session] connect ECONNREFUSED
  at errnoException  <net.js:904:11>
  at Object.afterConnect [as oncomplete]  <net.js:895:19>
```