New: Add no-extra-bind rule to flag unnecessary bind calls (fixes #982)

Fixes #982

This is my first pr here, if I'm doing something wrong, please tell me, and I'll rebase.
Before merge, [cli-engine.js](https://github.com/eslint/eslint/blob/master/lib/cli-engine.js#L175) should be fixed, it violates this new rule.
For short functions, I prefer not to use an exit-early approach. 

```js
If (top && top.fn !== node) {
    top.depth--;
}
```

In short functions, I want to know when I should do something as opposed to when I shouldn't.