Description of problem:
try to configure some options in /etc/virt-who.conf, only interval and hypervisor_id options can work well, other options are invalid. 

Version-Release number of selected component (if applicable):
virt-who-0.17-10.el7.noarch
subscription-manager-1.17.15-1.el7.x86_64
python-rhsm-1.17.9-1.el7.x86_64

How reproducible:
always

Steps to Reproduce:
1. Set interval in /etc/virt-who.conf
[global]
interval=3600

2. restart virt-who and check rhsm.log [PASS]
2016-09-19 05:37:14,823 [virtwho.main DEBUG] MainProcess(27629):MainThread @executor.py:run:171 - Starting infinite loop with 3600 seconds interval

3. Set hypervisor_id in /etc/virt-who.conf
[defaults]
hypervisor_id=hostname

4. restart virt-who and check rhsm.log [PASS]
    "localhost": [
        {
            "guestId": "737638c0-c0ae-b9f9-329b-42aec64933d5", 
            "state": 1, 
            "attributes": {
                "active": 1, 
                "virtWhoType": "xen"
            }
        }
    ]
}

5. set other options in /etc/virt-who.conf
[global]
interval=3600
#reporter_id=
debug=False
oneshot=True
log_per_config=False
log_dir=/tmp
log_file=virtwho.log
configs=/root/hyperv.conf

[defaults]
owner=ACME_Corporation
env=Library
hypervisor_id=hostname

6. restart virt-who and check virtwho.log as above settings [FAILED]
debug=False   ==> invalid
oneshot=True  ==> invalid
log_per_config=False       ==> invalid
log_dir=/tmp               ==> invalid
log_file=virtwho.log       ==> invalid
configs=/root/hyperv.conf  ==> invalid

owner=ACME_Corporation  ==> invalid
env=Library             ==> invalid