remove local.conf documentation for phases we don't implement
remove local.conf documentation for phases we don't implement

The local.conf docs talk about phases which don't exist for config
file processing, which makes it more confusing then it needs to be.

Change-Id: If7f9255eab0535c3d57a2fd5f1bc18ba4d0801aa

group-policy/devstack,richliu/devstack,group-policy/devstack,nawawi/openstack,bswartz/devstack,richliu/devstack,bswartz/devstack,dtroyer/devstack,openstack-dev/devstack,openstack-dev/devstack,dtroyer/devstack,noironetworks/devstack,nawawi/openstack,noironetworks/devstack