[SPARK-20942][WEB-UI] The title style about field is error in the history server web ui.

## What changes were proposed in this pull request?

1.The title style about field is error.
fix before:
![before](https://cloud.githubusercontent.com/assets/26266482/26661987/a7bed018-46b3-11e7-8a54-a5152d2df0f4.png)

fix after:
![fix](https://cloud.githubusercontent.com/assets/26266482/26662000/ba6cc814-46b3-11e7-8f33-cfd4cc2c60fe.png)

![fix1](https://cloud.githubusercontent.com/assets/26266482/26662080/3c732e3e-46b4-11e7-8768-20b5a6aeadcb.png)

executor-page style:
![executor_page](https://cloud.githubusercontent.com/assets/26266482/26662384/167cbd10-46b6-11e7-9e07-bf391dbc6e08.png)

2.Title text description, 'the application' should be changed to 'this application'.

3.Analysis of code:
 $('#history-summary [data-toggle="tooltip"]').tooltip();
The id of 'history-summary' is not there. We only contain id of 'history-summary-table'.

## How was this patch tested?

manual tests

Please review http://spark.apache.org/contributing.html before opening a pull request.

Author: guoxiaolong <guo.xiaolong1@zte.com.cn>
Author: 郭小龙 10207633 <guo.xiaolong1@zte.com.cn>
Author: guoxiaolongzte <guo.xiaolong1@zte.com.cn>

Closes #18170 from guoxiaolongzte/SPARK-20942.

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

@@ -20,47 +20,47 @@
   <thead>
     <tr>
       <th>
-        <span data-toggle="tooltip" data-placement="right" title="ID of the application.">
+        <span data-toggle="tooltip" data-placement="top" title="ID of this application.">
           App ID
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="above" title="Name of the application.">
+        <span data-toggle="tooltip" data-placement="top" title="Name of this application.">
           App Name
         </span>
       </th>
       <th class="attemptIDSpan">
-        <span data-toggle="tooltip" data-placement="above" title="The attempt ID of this application since one application might be launched several times">
+        <span data-toggle="tooltip" data-placement="top" title="The attempt ID of this application since one application might be launched several times">
           Attempt ID
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="right" title="Started time of this application.">
+        <span data-toggle="tooltip" data-placement="top" title="Started time of this application.">
           Started
         </span>
       </th>
       <th class="completedColumn">
-        <span data-toggle="tooltip" data-placement="above" title="The completed time of this application.">
+        <span data-toggle="tooltip" data-placement="top" title="The completed time of this application.">
           Completed
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="above" title="The duration time of this application.">
+        <span data-toggle="tooltip" data-placement="top" title="The duration time of this application.">
           Duration
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="right" title="The Spark user of this application">
+        <span data-toggle="tooltip" data-placement="top" title="The Spark user of this application">
           Spark User
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="above" title="The timestamp of the last updating on this application">
+        <span data-toggle="tooltip" data-placement="top" title="The timestamp of the last updating on this application">
           Last Updated
         </span>
       </th>
       <th>
-        <span data-toggle="tooltip" data-placement="above" title="Download the event log for this application">
+        <span data-toggle="tooltip" data-placement="top" title="Download the event log for this application">
           Event Log
         </span>
       </th>

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

@@ -195,7 +195,7 @@ $(document).ready(function() {
         }
 
         $(selector).DataTable(conf);
-        $('#hisotry-summary [data-toggle="tooltip"]').tooltip();
+        $('#history-summary [data-toggle="tooltip"]').tooltip();
       });
     });
 });