Fix the IE8 body re-assignment bug.
Fix the IE8 body re-assignment bug.

Before loading a suite Konacha replaces the `body` element to have a clean
slate:

```js
document.body = document.createElement('body');
```

However, IE8 does not support this and throws a `Member not found.` error.
Instead of assigning a new body element replace the current element in place.
This seems to satisfy all browsers, even IE8.

jfirebaugh/konacha,jfirebaugh/konacha,jfirebaugh/konacha