Description of problem:
I can successfully install atomic package from internal repo by yum, but atomic cmdline doesn't work because of missing PyYAML dependency.  

Version-Release number of selected component (if applicable):
$ rpm -q atomic docker kernel
atomic-1.10.3-1.el7.x86_64
docker-1.10.3-26.el7.x86_64
kernel-3.10.0-327.el7.x86_64

$ cat /etc/redhat-release 
Red Hat Enterprise Linux Server release 7.2 (Maipo)

How reproducible:
always

Steps to Reproduce:
1. yum install -y atomic 
2. atomic -h


Actual results:

$ atomic -h
Traceback (most recent call last):
  File "/usr/bin/atomic", line 31, in <module>
    import Atomic
  File "/usr/lib/python2.7/site-packages/Atomic/__init__.py", line 1, in <module>
    from .pulp import PulpServer, PulpConfig
  File "/usr/lib/python2.7/site-packages/Atomic/pulp.py", line 11, in <module>
    from . import util
  File "/usr/lib/python2.7/site-packages/Atomic/util.py", line 10, in <module>
    from yaml import load as yaml_load
ImportError: No module named yaml


Expected results:
Fix it.

Additional info:

$ rpm -qRp atomic-1.10.3-1.el7.x86_64.rpm 
/bin/bash
/usr/bin/python2
config(atomic) = 1:1.10.3-1.el7
dbus
docker
polkit
python(abi) = 2.7
python-docker-py >= 1.7.2-1
python-requests
python-setuptools
python-six >= 1.3.0
python-websocket-client >= 0.11.0
rpm-python
rpmlib(CompressedFileNames) <= 3.0.4-1
rpmlib(FileDigests) <= 4.6.0-1
rpmlib(PartialHardlinkSets) <= 4.0.4-1
rpmlib(PayloadFilesHavePrefix) <= 4.0-1
setup
skopeo >= 1:0.1.13-1.el7
rpmlib(PayloadIsXz) <= 5.2-1