=> http://efcl.info/2014/0518/res3905/

Github:time-format-changer.user.js

// ==UserScript==
// @id             github.com-ff599db1-47d8-b14f-83b4-3e345f6d67e3@http://efcl.info/
// @name           Github:time-format-changer
// @version        1.0
// @namespace      http://efcl.info/
// @author         azu
// @description    
// @include        https://github.com/*
// @run-at         document-end
// @grant       none
// ==/UserScript==

var $ = unsafeWindow.$;
var titleFormat = "%Y-%m-%d %H:%M";
var toArray = Function.prototype.call.bind(Array.prototype.slice);
var relative = /ago/i;
function _update(body){
    var times = body.getElementsByTagName("time");
    toArray(times).forEach(function(timeElement){
        if(!relative.test(timeElement.textContent)){
            timeElement.setAttribute("is","");
            timeElement.setAttribute("title-format",titleFormat);
            var title = timeElement.getAttribute("title").split(":");
            title.pop();
            timeElement.textContent = title.join(":");
        }
    });
}
function update(body){
    requestAnimationFrame(function(){ _update(body); });   
}
$(document).on('pjax:end', function pjaxEnd() {
    update(document.body);
});
var addFilterHandler = function(evt){
  var node = evt.target;
  update(node);
}
document.body.addEventListener('AutoPagerize_DOMNodeInserted', addFilterHandler, false);
// MAIN =
update(document.body);