[SPARK-6694][SQL]SparkSQL CLI must be able to specify an option --database on the command line.

SparkSQL CLI has an option --database as follows.
But, the option --database is ignored.

```
$ spark-sql --help
:
CLI options:
    :
    --database <databasename>     Specify the database to use
```

Author: Jin Adachi <adachij2002@yahoo.co.jp>
Author: adachij <adachij@nttdata.co.jp>

Closes #5345 from adachij2002/SPARK-6694 and squashes the following commits:

8659084 [Jin Adachi] Merge branch 'master' of https://github.com/apache/spark into SPARK-6694
0301eb9 [Jin Adachi] Merge branch 'master' of https://github.com/apache/spark into SPARK-6694
df81086 [Jin Adachi] Modify code style.
846f83e [Jin Adachi] Merge branch 'master' of https://github.com/apache/spark into SPARK-6694
dbe8c63 [Jin Adachi] Change file permission to 644.
7b58f42 [Jin Adachi] Merge branch 'master' of https://github.com/apache/spark into SPARK-6694
c581d06 [Jin Adachi] Add an option --database test
db56122 [Jin Adachi] Merge branch 'SPARK-6694' of https://github.com/adachij2002/spark into SPARK-6694
ee09fa5 [adachij] Merge branch 'master' into SPARK-6694
c804c03 [adachij] SparkSQL CLI must be able to specify an option --database on the command line.