Fix service-template.py doesn't honor -c parameter
Fix service-template.py doesn't honor -c parameter

Before this fix the config file path was forced.
This patch also check that the config file exists and
is correctly parsed.

Change-Id: I34c80e66be972a145a78e075710b53930790b598

vpramo/contrail-controller,nischalsheth/contrail-controller,tcpcloud/contrail-controller,vmahuli/contrail-controller,eonpatapon/contrail-controller,Juniper/contrail-dev-controller,sajuptpm/contrail-controller,codilime/contrail-controller,cloudwatt/contrail-controller,codilime/contrail-controller,cloudwatt/contrail-controller,reiaaoyama/contrail-controller,varunarya10/contrail-controller,tcpcloud/contrail-controller,sajuptpm/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,srajag/contrail-controller,varunarya10/contrail-controller,facetothefate/contrail-controller,hthompson6/contrail-controller,reiaaoyama/contrail-controller,varunarya10/contrail-controller,tcpcloud/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,vpramo/contrail-controller,codilime/contrail-controller,rombie/contrail-controller,vmahuli/contrail-controller,varunarya10/contrail-controller,Juniper/contrail-dev-controller,Juniper/contrail-dev-controller,hthompson6/contrail-controller,eonpatapon/contrail-controller,DreamLab/contrail-controller,cloudwatt/contrail-controller,DreamLab/contrail-controller,eonpatapon/contrail-controller,vmahuli/contrail-controller,numansiddique/contrail-controller,nischalsheth/contrail-controller,cloudwatt/contrail-controller,rombie/contrail-controller,varunarya10/contrail-controller,cloudwatt/contrail-controller,eonpatapon/contrail-controller,Juniper/contrail-dev-controller,nischalsheth/contrail-controller,srajag/contrail-controller,vpramo/contrail-controller,srajag/contrail-controller,vpramo/contrail-controller,facetothefate/contrail-controller,nischalsheth/contrail-controller,srajag/contrail-controller,tcpcloud/contrail-controller,codilime/contrail-controller,numansiddique/contrail-controller,sajuptpm/contrail-controller,rombie/contrail-controller,DreamLab/contrail-controller,vmahuli/contrail-controller,sajuptpm/contrail-controller,Juniper/contrail-dev-controller,tcpcloud/contrail-controller,DreamLab/contrail-controller,reiaaoyama/contrail-controller,hthompson6/contrail-controller,vpramo/contrail-controller,reiaaoyama/contrail-controller,sajuptpm/contrail-controller,tcpcloud/contrail-controller,rombie/contrail-controller,codilime/contrail-controller,numansiddique/contrail-controller,facetothefate/contrail-controller,facetothefate/contrail-controller,vmahuli/contrail-controller,DreamLab/contrail-controller,numansiddique/contrail-controller,numansiddique/contrail-controller,codilime/contrail-controller,eonpatapon/contrail-controller,reiaaoyama/contrail-controller,facetothefate/contrail-controller,rombie/contrail-controller,hthompson6/contrail-controller,eonpatapon/contrail-controller,hthompson6/contrail-controller,nischalsheth/contrail-controller,nischalsheth/contrail-controller,sajuptpm/contrail-controller,srajag/contrail-controller