nicer dates in timeline header

src/common/utilities.js

@@ -211,3 +211,19 @@ export function findDescriptionInFilterTree (key, node) {
   if (descs.length !== 1) return false
   return descs[0]
 }
+
+export function makeNiceDate (datetime) {
+  if (datetime === null) return null
+  // see https://stackoverflow.com/questions/3552461/how-to-format-a-javascript-date
+  const dateTimeFormat = new Intl.DateTimeFormat(
+    'en',
+    { year: 'numeric', month: 'long', day: '2-digit' }
+  )
+  const [
+    { value: month },,
+    { value: day },,
+    { value: year }
+  ] = dateTimeFormat.formatToParts(datetime)
+
+  return `${day} ${month}, ${year}`
+}