Float Methods: No Literal-Specific Methods

Float has zero literal-specific methods, but Math module has float operations:

```js
3.14.round()  // Doesn't exist
Math.round(3.14)  // Must use this
```

- Add common methods to Float:
  ```js
  3.14.round()      // Returns 3
  3.14.ceil()       // Returns 4
  3.14.floor()      // Returns 3
  3.14.abs()        // Returns 3.14
  (-3.14).abs()     // Returns 3.14
  ```
