Add ODL_BOOT_WAIT_URL to odl-releases/beryllium-snapshot-0.4.0
Add ODL_BOOT_WAIT_URL to odl-releases/beryllium-snapshot-0.4.0

Thisl will make stacking of ODL that release a lot faster, since
it waits only as much as needed for ODL to become operational.

Change-Id: I9667251ce2192c4e5fa7861123e9d06bc1aea556

openstack/networking-odl,flavio-fernandes/networking-odl,FedericoRessi/networking-odl,FedericoRessi/networking-odl,openstack/networking-odl,openstack/networking-odl,flavio-fernandes/networking-odl