Fix translation for Rosh Hashana

The event for Rosh Hashana is now translated correctly into the active locale.

Thanks to @ilayDev for finding this bug #10

  const RH = new HDate(1, months.TISHREI, 5749);
  const options = {start: RH, end: RH};
  const ev = HebrewCalendar.calendar(options)[0];
  t.is(ev.render('en'), 'Rosh Hashana 5749');
  t.is(ev.render('he'), 'רֹאשׁ הַשָּׁנָה 5749');