Since we are using bash syntax in some of the element fragments,
we should make sure we use bash for all of them, so that things don't
break on systems where /bin/sh != /bin/bash.
Change-Id: If2f043c57aa4e1492b7f9839213ef6123f683612
Rather than dublicating code to implement rhel or any
other derivitive, this patch introduces an rpm-distro
element that should be used as a dependency.
Change-Id: I8a92bb041764d03f430b438f0013704f79a8674c