Description of problem:
virt-builder doesn't run any commands on system that it is building - if you specify command to run with --run-command or packages to install with --install (or even --selinux-relabel), it doesn't fail during building that image, but it doesn't seem to run that command either.

For example, if you run:

virt-builder -x -v fedora-22 --install vim --root-password password:weakpassword -o disk.img

vim isn't installed on output disk image.

Version-Release number of selected component (if applicable):
virt-builder 1.30.1fedora=22,release=2.fc22,libvirt

How reproducible:
Always.

Steps to Reproduce:
1. Run 'virt-builder -x -v fedora-22 --install vim --root-password password:weakpassword -o disk.img'
2. Boot disk.img: 'qemu-kvm disk.img'
3. Observe that vim isn't installed.