[SPARK-2458] Make failed application log visible on History Server

Enabled HistoryServer to show incomplete applications.
We can see the log for incomplete applications by clicking the bottom link.

Author: Masayoshi TSUZUKI <tsudukim@oss.nttdata.co.jp>

Closes #3467 from tsudukim/feature/SPARK-2458-2 and squashes the following commits:

76205d2 [Masayoshi TSUZUKI] Fixed and added test code.
29a04a9 [Masayoshi TSUZUKI] Merge branch 'master' of github.com:tsudukim/spark into feature/SPARK-2458-2
f9ef854 [Masayoshi TSUZUKI] Added space between "if" and "(". Fixed "Incomplete" as capitalized in the web UI. Modified double negative variable name.
9b465b0 [Masayoshi TSUZUKI] Modified typo and better implementation.
3ed8a41 [Masayoshi TSUZUKI] Modified too long lines.
08ea14d [Masayoshi TSUZUKI] [SPARK-2458] Make failed application log visible on History Server