service_plugins must not be list with empty string

Change-Id: Ib2646588add5e0e09c6af5f14f6870fa911ee601
Fixes: rhbz#1040585
CONFIG_NEUTRON_LBAAS_HOSTS should be empty in allinone

Change-Id: Ia087636f2556a67b735c0ec255d6e3bf7f0ca57d
Fixes: rhbz#1040585
Merge "service_plugins must not be list with empty string"
Merge "CONFIG_NEUTRON_LBAAS_HOSTS should be empty in allinone"