system: return uptime and reboot required

src/system.js

@@ -2,7 +2,7 @@
 
 exports = module.exports = {
     reboot,
-    isRebootRequired,
+    getInfo,
     getUbuntuVersion,
     getDisks,
     getSwaps,
@@ -279,9 +279,15 @@ async function reboot() {
     if (error) debug('reboot: could not reboot. %o', error);
 }
 
-async function isRebootRequired() {
+async function getInfo() {
     // https://serverfault.com/questions/92932/how-does-ubuntu-keep-track-of-the-system-restart-required-flag-in-motd
-    return fs.existsSync('/var/run/reboot-required');
+    const rebootRequired = fs.existsSync('/var/run/reboot-required');
+    const uptime = safe.child_process.execSync('uptime -s', { encoding: 'utf8' });
+
+    return {
+        uptime,
+        rebootRequired
+    };
 }
 
 async function startUpdateDiskUsage() {
@@ -330,7 +336,7 @@ async function getBlockDevices() {
 }
 
 async function checkRebootRequired() {
-    const rebootRequired = await isRebootRequired();
+    const { rebootRequired } = await getInfo();
     if (rebootRequired) {
         await notifications.alert(notifications.ALERT_REBOOT, 'Reboot Required', 'To finish ubuntu security updates, a reboot is necessary.', { persist: true });
     } else {