[SPARK-18837][WEBUI] Very long stage descriptions do not wrap in the UI

## What changes were proposed in this pull request?

This issue was reported by wangyum.

In the AllJobsPage, JobPage and StagePage, the description length was limited before like as follows.

![ui-2 0 0](https://cloud.githubusercontent.com/assets/4736016/21319673/8b225246-c651-11e6-9041-4fcdd04f4dec.gif)

But recently, the limitation seems to have been accidentally removed.

![ui-2 1 0](https://cloud.githubusercontent.com/assets/4736016/21319825/104779f6-c652-11e6-8bfa-dfd800396352.gif)

The cause is that some tables are no longer `sortable` class although they were, and `sortable` class does not only mark tables as sortable but also limited the width of their child `td` elements.
The reason why now some tables are not `sortable` class is because another sortable mechanism was introduced by #13620 and #13708 with pagination feature.

To fix this issue, I've introduced new class `table-cell-width-limited` which limits the description cell width and the description is like what it was.

<img width="1260" alt="2016-12-20 1 00 34" src="https://cloud.githubusercontent.com/assets/4736016/21320478/89141c7a-c654-11e6-8494-f8f91325980b.png

">

## How was this patch tested?

Tested manually with my browser.

Author: Kousuke Saruta <sarutak@oss.nttdata.co.jp>

Closes #16338 from sarutak/SPARK-18837.

(cherry picked from commit f2ceb2ab)
Signed-off-by: Sean Owen <sowen@cloudera.com>