Rename virtualbox to virtualbox-iso
Rename virtualbox to virtualbox-iso

Packer 0.5.0 is using virtualbox-iso now

Signed-off-by: Andrea Law <d769b6546cf1ff4ea5640f22f22af90f587f1c59@pivotallabs.com>

voelzmo/bosh-packer-templates,cloudfoundry/bosh-packer-templates,voelzmo/bosh-packer-templates,Altoros/bosh-packer-templates,cloudfoundry/bosh-packer-templates,Altoros/bosh-packer-templates