`RoundingMode`

Specifies a rounding behavior for discarding precision of Floats. A rounding mode dictates how the least significant returned digit of a rounded result is calculated.

Ceiling |
Rounding mode to round towards positive infinity. |

Down |
Rounding mode to round towards zero. |

Floor |
Rounding mode to round towards negative infinity. |

HalfDown |
Rounding mode to round towards “nearest neighbor” unless both neighbors are equidistant, in which case round towards zero. |

HalfEven |
Rounding mode to round towards the “nearest neighbor” unless both neighbors are equidistant, in which case, round towards the even neighbor. |

HalfUp |
Rounding mode to round towards “nearest neighbor” unless both neighbors are equidistant, in which case round away from zero. |

Up |
Rounding mode to round away from zero. |

The rounding modes correspond to the ones found in `java.math.RoundingMode`

(https://docs.oracle.com/javase/8/docs/api/java/math/RoundingMode.html).

```
type RoundingMode
| Ceiling
| Down
| Floor
| HalfDown
| HalfEven
| HalfUp
| Up
```

Used in Math::round