packaging: when using services, always use files in execCmd (#737814)
packaging: when using services, always use files in execCmd (#737814)

http://bugzilla.redhat.com/737814

When starting/stopping a service, we will always call execCmd
with usePipeFiles=True in order to avoid fork/fork/hang problems
(subprocess hell.)

Change-Id: I0309699a0fb195611c7e9c60eea057d64a2b0ba1

eayun/ovirt-engine,halober/ovirt-engine,Dhandapani/gluster-ovirt,yapengsong/ovirt-engine,OpenUniversity/ovirt-engine,OpenUniversity/ovirt-engine,zerodengxinchao/ovirt-engine,eayun/ovirt-engine,OpenUniversity/ovirt-engine,walteryang47/ovirt-engine,derekhiggins/ovirt-engine,halober/ovirt-engine,yingyun001/ovirt-engine,zerodengxinchao/ovirt-engine,derekhiggins/ovirt-engine,zerodengxinchao/ovirt-engine,eayun/ovirt-engine,yapengsong/ovirt-engine,zerodengxinchao/ovirt-engine,yingyun001/ovirt-engine,yingyun001/ovirt-engine,Dhandapani/gluster-ovirt,walteryang47/ovirt-engine,eayun/ovirt-engine,walteryang47/ovirt-engine,halober/ovirt-engine,walteryang47/ovirt-engine,halober/ovirt-engine,yapengsong/ovirt-engine,derekhiggins/ovirt-engine,OpenUniversity/ovirt-engine,yapengsong/ovirt-engine,derekhiggins/ovirt-engine,eayun/ovirt-engine,Dhandapani/gluster-ovirt,yingyun001/ovirt-engine,OpenUniversity/ovirt-engine,yapengsong/ovirt-engine,Dhandapani/gluster-ovirt,walteryang47/ovirt-engine,zerodengxinchao/ovirt-engine,yingyun001/ovirt-engine,Dhandapani/gluster-ovirt