New methods for Intervals

[Quantumplation]

I'd like to propose adding some new methods to the standard library for comparing intervals.

is_entirely_after<T>(interval: Interval<T>, point: T) -> Bool // Returns true if the entire interval is after `point`
is_entirely_before<T>(interval: Interval<T>, point: T) -> Bool // Returns true if the entire interval is before `point`

The stdlib has after and before, but these construct half-open intervals instead of doing comparisons.

[Quantumplation]

(happy to submit a PR, just wanted to check that it was welcome first)

[KtorZ]

Sounds like something we would welcome :)

[Quantumplation]

Oh, looks like I can't yet, because we can't compare traits; I'll implement the Int version for now

[rvcas]

The pattern so far has been to accept a lambda that returns Ordering which is in the prelude

[Quantumplation]

These are merged so I'm gunna close the discussion