update dateTime so that it works correctly for all locales

including those that don't zero-pad their hours or use 24-hour time
The old approach here, which uses substr to cut off the
toLocaleTimeString() output at 5 characters does not work
for locales with formatting
    9:20:35 PM
It incorrectly grabs the first 5 chars including the trailing colon
    9:20:
The new approach here will instead return
    09:20 PM
for these locales while still producing sensible output
for 24-hour locales

lib/IHP/static/helpers.js

@@ -32,7 +32,7 @@ function initTime() {
 
     document.querySelectorAll(".date-time").forEach(function(elem){
         var date = new Date(elem.dateTime);
-        elem.innerHTML = date.toLocaleDateString() +", " + date.toLocaleTimeString().substr(0,5);
+        elem.innerHTML = date.toLocaleDateString() +", " + date.toLocaleTimeString([], {hour: '2-digit', minute:'2-digit'});
     });
 
     document.querySelectorAll(".date").forEach(function(elem){