[SPARK-13481] Desc order of appID by default for history server page.

## What changes were proposed in this pull request?

Now by default, it shows as ascending order of appId. We might prefer to display as descending order by default, which will show the latest application at the top.

## How was this patch tested?

Manual tested. See screenshot below:

![desc-sort](https://cloud.githubusercontent.com/assets/11683054/13307473/102f4cf8-db31-11e5-8dd5-391edbf32f0d.png)

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

Closes #11357 from zhuoliu/13481.