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
Git isn't a dependency of this element, but is a dependency of pbr
if you are doing pip install on a git cloned directoy, because this
looks to be a fairly common pattern it makes sense to have git on the
target image.
Change-Id: I49ee3fa4eac493b9dfa379a674ab9b3390cfc89a