CLOUDSTACK-7852: EN-US, SC: CentOS CLI & Windows OS: Key translation
fails on the Numeric Del. key for US 101 keyboard.
CLOUDSTACK-7854: Don't have CentOS 5.3 built-in template when we've 5.6

Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>
(cherry picked from commit 318f7159a0f1456e1058e6dee43887b4683310de)
Signed-off-by: Rohit Yadav <rohit.yadav@shapeblue.com>