adblockplusopera: Port UI code from Chrome

options/time.js

-const updateTime = {
-        display: function() {
-                var elements = document.getElementsByClassName('update_time');
-                for(i = 0; i < elements.length; i++) {
-                        var key = elements[i].parentNode.id;
-                        if(preferences.exist(key + '-time')) {
-                                var difference = getTime() - preferences.int(key + '-time');
-                                elements[i].innerHTML = ' ' + this.string(difference);
-                        }
-                        else {
-                                elements[i].innerHTML = ' ' + translate.get('update_just');
-                        }
-                }
-        },
-        string: function(time) {
-                if(time < 60000) //< 1 minute
-                        return (translate.get('update_just'));
-                if(time < 2*60000) //< 2 minutes
-                        return (translate.get('update_minute'));
-                if(time < 60*60000) //< 1 hour
-                        return (translate.get('update_minutes')).replace(/%/, Math.floor(time / (60000)));
-                if(time < 2*60*60000) //< 2 hours
-                        return (translate.get('update_hour'));
-                if(time < 24*60*60000) //< 1 day
-                        return (translate.get('update_hours')).replace(/%/, Math.floor(time / (60*60000)));
-                if(time < 2*24*60*60000) //< 2 days
-                        return (translate.get('update_day'));
-                if(time < 30*24*60*60000) //< 1 month
-                        return (translate.get('update_days')).replace(/%/, Math.floor(time / (24*60*60000)));
-                else //> 1 month
-                        return (translate.get('update_old'));
-        }
-};
-
-updateTime.display();
-window.setInterval("updateTime.display();", 5000)