Description of problem:
unpersist file fails if not using full file path


[root@puma26 tmp]# cd /etc/sysconfig/network-scripts/
[root@puma26 network-scripts]# touch test
[root@puma26 network-scripts]# persist test
Successfully persisted: test
[root@puma26 network-scripts]# unpersist test
File not explicitly persisted: test
[root@puma26 network-scripts]# unpersist /etc/sysconfig/network-scripts/test 
/etc/sysconfig/network-scripts/test successully unpersisted


Version-Release number of selected component (if applicable):
Red Hat Enterprise Virtualization Hypervisor release 7.1
Red Hat Enterprise Virtualization Hypervisor release 6.7 (20150828.0.el6ev)

How reproducible:
100%

Steps to Reproduce:
1. cd /etc/sysconfig/network-scripts/
2. touch test 
3. persist test
4. unpersist test



Additional info:
in /usr/sbin/unpersist
if not conf.exists(path) probeblly returs False when not using full path

from ovirt.node.utils import fs
conf = fs.Config()
conf.exists('/etc/sysconfig/network-scripts/test')
True
>>> conf.exists('network-scripts/test')
False

os.system('pwd')
/etc/sysconfig

os.path.isfile('network-scripts/test')
True