packaging: Added function to fetch password from pgpass
packaging: Added function to fetch password from pgpass

* Added getDbPassword function that gets a password for
a specific user.

Change-Id: I3b2f906f26a47c982ebbad6a8da6a943fba507f5
Signed-off-by: Alex Lourie <9b6bd04ec8ec26165955e5c2df3f157a49c49dc0@redhat.com>

paramite/packstack,openstack/packstack,weshayutin/packstack,mahak/packstack,fr34k8/packstack,radez/packstack,derekhiggins/packstack,alincalinciuc/packstack,xbezdick/packstack,larsks/packstack,derekhiggins/packstack,bcrochet/packstack,openstack/packstack,xbezdick/packstack,spkane/packstack,radez/packstack,pkilambi/packstack,mahak/packstack,bcrochet/packstack,weshayutin/packstack,bcrochet/packstack,fr34k8/packstack,derekhiggins/packstack,harveyzh/packstack,radez/packstack,stackforge/packstack,pkilambi/packstack,palmer159/openstack-test,palmer159/openstack-test,imcsk8/packstack,xbezdick/packstack,imcsk8/packstack,imcsk8/packstack,spkane/packstack,larsks/packstack,alincalinciuc/packstack,harveyzh/packstack,alincalinciuc/packstack,palmer159/openstack-test,openstack/packstack,paramite/packstack,paramite/packstack,harveyzh/packstack,weshayutin/packstack,spkane/packstack,mahak/packstack,larsks/packstack,pkilambi/packstack,fr34k8/packstack,stackforge/packstack,stackforge/packstack