formatNumber to accept maximumFractionDigits=0

Logic error in the options processing that prevent
maximumFractionDigits=0 from being passed into internal methods
properly, resulting in maximumFractionDigits being set to default
value. Fixed the logic and added tests to ensure fraction truncation.

```Globalize.formatNumber(3.14159, {maximumFractionDigits: 0}) === "3"```
@baohouse, thanks for your fix.

The `||` verification obviously isn't appropriate for number variables that include `0` in its range. `minimumIntegerDigits` (the minimum digits for the integer part), `minimumSignificantDigits` and `maximumSignificantDigits` are `> 0`. Although, `minimumFractionDigits` and `maximumFractionDigits` are `>= 0`.

So, 1st thing, we should fix it for `minimumFractionDigits` as well (minimumFractionDigits = 0 means "show its integer part only"). Can you fix it too?

Secondly, I'm inclined to use `hasOwnProperty` instead.

@scottgonzalez, @jzaefferer any thoughts?