Improve help text for allocation_ratio_opts
Improve help text for allocation_ratio_opts

This commit adds additional help text to allocation_
ratio_opts
Blueprint centralize-config-options-newton
Closes-Bug: #1590133
Change-Id: I4654bb26184a2a993aab9476e5d303f5f00803e0

cloudbase/nova,hanlind/nova,vmturbo/nova,sebrandon1/nova,rajalokan/nova,jianghuaw/nova,jianghuaw/nova,vmturbo/nova,rahulunair/nova,openstack/nova,rajalokan/nova,Juniper/nova,Juniper/nova,mahak/nova,rahulunair/nova,mikalstill/nova,gooddata/openstack-nova,klmitch/nova,rajalokan/nova,vmturbo/nova,openstack/nova,mikalstill/nova,cloudbase/nova,alaski/nova,phenoxim/nova,gooddata/openstack-nova,jianghuaw/nova,Juniper/nova,klmitch/nova,klmitch/nova,vmturbo/nova,gooddata/openstack-nova,Juniper/nova,hanlind/nova,rajalokan/nova,mikalstill/nova,cloudbase/nova,gooddata/openstack-nova,rahulunair/nova,mahak/nova,phenoxim/nova,openstack/nova,klmitch/nova,mahak/nova,jianghuaw/nova,sebrandon1/nova,alaski/nova,sebrandon1/nova,hanlind/nova