High: PE: Implement promote/demote ordering for cloned groups
Added constraints to ensure groups where promoted and demoted in the correct
order (relative to the other cloned instances)
Also allowed the group's meta actions to be included in the graph without
making them mandatory (which would have caused the whole group to restart).
This had positive effects on the way cloned groups were started/stopped.

Mercurial revision: 76206b773b0545a5860bb10744fa4531655d5262