don't add /etc/hosts record if ip is empty (issue #1146)
don't add /etc/hosts record if ip is empty (issue #1146)

Signed-off-by: Andrei Ushakov <efd795d3b11afef0b4e35dea2c6011226886bd28@netflix.com>

cpuguy83/docker,cpuguy83/docker,nalind/docker,flavio/docker,konstruktoid/docker-upstream,djs55/docker,yosifkit/docker,docker/docker,cpuguy83/docker,AkihiroSuda/docker,paralin/docker,konstruktoid/docker-upstream,paralin/docker,jimjag/docker,gnailuy/docker,Mokolea/docker,bearstech/moby,moul/docker,Mokolea/docker,jimjag/docker,AkihiroSuda/docker,moby/moby,docker/docker,vdemeester/docker,AkihiroSuda/docker,djs55/docker,nawawi/docker,nalind/docker,konstruktoid/docker-upstream,Ramzec/docker,moby/moby,jthelin/docker,konstruktoid/docker-upstream,yosifkit/docker,bearstech/moby,AkihiroSuda/docker,moul/docker,trebonian/docker,nawawi/docker,flavio/docker,gnailuy/docker,nalind/docker,jameszhan/docker,Mokolea/docker,yosifkit/docker,nalind/docker,trebonian/docker,thaJeztah/docker,yosifkit/docker,vdemeester/docker,moul/docker,mahak/docker,bearstech/moby,paralin/docker,thaJeztah/docker,flavio/docker,flavio/docker,thaJeztah/docker,jameszhan/docker,mahak/docker,docker/docker,trebonian/docker,nawawi/docker,moul/docker,jimjag/docker,moby/moby,jameszhan/docker,jthelin/docker,mahak/docker,paralin/docker,djs55/docker,Ramzec/docker,gnailuy/docker,vdemeester/docker,Mokolea/docker,gnailuy/docker,Ramzec/docker,cpuguy83/docker,jimjag/docker,bearstech/moby,thaJeztah/docker,moby/moby,mahak/docker,nawawi/docker,trebonian/docker,Ramzec/docker