Added "App ID column" to HistoryPage

Author: sarutak

core/src/main/scala/org/apache/spark/deploy/history/HistoryPage.scala

@@ -67,6 +67,7 @@ private[spark] class HistoryPage(parent: HistoryServer) extends WebUIPage("") {
   }
 
   private val appHeader = Seq(
+    "App ID",
     "App Name",
     "Started",
     "Completed",
@@ -81,7 +82,8 @@ private[spark] class HistoryPage(parent: HistoryServer) extends WebUIPage("") {
     val duration = UIUtils.formatDuration(info.endTime - info.startTime)
     val lastUpdated = UIUtils.formatDate(info.lastUpdated)
     <tr>
-      <td><a href={uiAddress}>{info.name}</a></td>
+      <td><a href={uiAddress}>{info.id}</a></td>
+      <td>{info.name}</td>
       <td>{startTime}</td>
       <td>{endTime}</td>
       <td>{duration}</td>