templates: For Debian 7.0 rc1-amd64 select console keymap 'us'

Signed-off-by: Rohit Yadav <bhaisaab@apache.org>
Merge pull request #590 from bhaisaab/master

For amd64 Debian 7.0 rc1 template, fix console keymap as 'us'
Modified CentOS 5.8 netboot to use vault for stage2 image