core:  When there is no post upgrade files the ...
core:  When there is no post upgrade files the ...

When there is no post upgrade files the creation of the database
repeats forever.

Adding a check if directory exists before getting pre/post upgrade
scripts.

Change-Id: I476b533b6df9814cfe8970dac0d3e71bc0d90017
Signed-off-by: Eli Mesika <dc8a2a200abf66067593de2e51fee9376f06ea0f@redhat.com>
Bug-Url:https://bugzilla.redhat.com/886131

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