Fix unknown format err while check-update on RHEL6.5

[sadayuki-matsuno]

I fixed the following error of scaning RHEL servers.

 % go run main.go scan
INFO[0000] Start scanning
INFO[0000] config: /Users/matsunosadayuki/go/plugins/src/github.com/future-architect/vuls/config.toml
INFO[0000] cve-dictionary: http://127.0.0.1:1323
[Jun  5 12:59:22]  INFO [localhost] Validating Config...
[Jun  5 12:59:22]  INFO [localhost] Detecting Server OS...
[Jun  5 12:59:26]  INFO [localhost] (1/1) Detected vuls-dev-rhel: rhel 6.5
[Jun  5 12:59:26]  INFO [localhost] Detecting Container OS...
[Jun  5 12:59:26]  INFO [localhost] Scanning vulnerabilities...
[Jun  5 12:59:26]  INFO [localhost] Check required packages for scanning...
[Jun  5 12:59:26]  INFO [localhost] Scanning vulnerable OS packages...
[Jun  5 13:00:36] ERROR [vuls-dev-rhel] Failed to scan vulnerable packages
[Jun  5 13:00:36] ERROR [localhost] Failed to scan. err: ec2-user@54.199.248.145:22: Failed to parse LANG=en_US.UTF-8 yum --color=never check-update. err: Unknown format: Red_Hat_Enterprise_Linux-Release_Notes-6-en-US.noarch

This error is caused by check-update format.
https://github.com/future-architect/vuls/blob/master/scan/redhat.go#L265
Specifically, vuls should check a few lines when the line field is not 3.

[sadayuki-matsuno]

add this format into redhat_test.go
and fix typo.

[sadayuki-matsuno]

I changed ssh terminal width to avoid this error.
Please check this.

[kotakanbe]

Many Thanks!!