[SPARK-13364] Sort appId as num rather than str in history page.

## What changes were proposed in this pull request?

History page now sorts the appID as a string, which can lead to unexpected order for the case "application_11111_9" and "application_11111_20".
Add a new sort type called appId-numeric can fix it.

## How was the this patch tested?
This patch was manually tested with UI. See the screenshot below:
![sortappidbetter](https://cloud.githubusercontent.com/assets/11683054/13185564/7f941a16-d707-11e5-8fb7-0316368d3030.png)

Author: zhuol <zhuol@yahoo-inc.com>

Closes #11259 from zhuoliu/13364.

core/src/main/resources/org/apache/spark/ui/static/historypage-template.html

@@ -64,7 +64,7 @@
   <tbody>
   {{#applications}}
     <tr>
-      <td class="rowGroupColumn"><a href="/history/{{id}}/{{num}}/jobs/">{{id}}</a></td>
+      <td class="rowGroupColumn"><span title="{{id}}"><a href="/history/{{id}}/{{num}}/jobs/">{{id}}</a></span></td>
       <td class="rowGroupColumn">{{name}}</td>
       {{#attempts}}
       <td class="attemptIDSpan"><a href="/history/{{id}}/{{attemptId}}/jobs/">{{attemptId}}</a></td>

core/src/main/resources/org/apache/spark/ui/static/historypage.js

@@ -37,6 +37,22 @@ function formatDuration(milliseconds) {
   return hours.toFixed(1) + " h";
 }
 
+function makeIdNumeric(id) {
+  var strs = id.split("_");
+  if (strs.length < 3) {
+    return id;
+  }
+  var appSeqNum = strs[2];
+  var resl = strs[0] + "_" + strs[1] + "_";
+  var diff = 10 - appSeqNum.length;
+  while (diff > 0) {
+      resl += "0"; // padding 0 before the app sequence number to make sure it has 10 characters
+      diff--;
+  }
+  resl += appSeqNum;
+  return resl;
+}
+
 function formatDate(date) {
   return date.split(".")[0].replace("T", " ");
 }
@@ -62,6 +78,21 @@ jQuery.extend( jQuery.fn.dataTableExt.oSort, {
     }
 } );
 
+jQuery.extend( jQuery.fn.dataTableExt.oSort, {
+    "appid-numeric-pre": function ( a ) {
+        var x = a.match(/title="*(-?[0-9a-zA-Z\-\_]+)/)[1];
+        return makeIdNumeric(x);
+    },
+
+    "appid-numeric-asc": function ( a, b ) {
+        return ((a < b) ? -1 : ((a > b) ? 1 : 0));
+    },
+
+    "appid-numeric-desc": function ( a, b ) {
+        return ((a < b) ? 1 : ((a > b) ? -1 : 0));
+    }
+} );
+
 $(document).ajaxStop($.unblockUI);
 $(document).ajaxStart(function(){
     $.blockUI({ message: '<h3>Loading history summary...</h3>'});
@@ -109,7 +140,7 @@ $(document).ready(function() {
         var selector = "#history-summary-table";
         var conf = {
                     "columns": [
-                        {name: 'first'},
+                        {name: 'first', type: "appid-numeric"},
                         {name: 'second'},
                         {name: 'third'},
                         {name: 'fourth'},