Function covid19db::dateutil::nd_to_day

pub fn nd_to_day(nd: &NaiveDate) -> i32

Convert a NaiveDate to a i32-based Julian day

use covid19db::dateutil::*;
use chrono::prelude::*;

assert_eq!(nd_to_day(&NaiveDate::from_ymd(2015, 3, 14)), 2457096);