Function isNotNegative

isNotNegative(value?: number): boolean
Returns whether the given value is not negative
Parameters
- Optionalvalue: number
  the number value to check
Returns boolean
whether the given value is not negative
Author
David Hsing
Example
```
isNotNegative(1);    // true
isNotNegative(0);    // true
isNotNegative(-1);    // false
```