Remove Numeric.format and Numberic#format monkey patch.

Git grep cannot help me find where this is used.

Let's remove this if it's not used.

It was added before I started at MIQ and has only been moved from one file to another.

```
commit 7987c43e93c5207eb76d70f8ae58d280fa5649c1
Date:   Wed Apr 18 13:55:29 2007 +0000

    Bring ntfs up to date.
```