added a dual layer dual PDU fencing example to ch-Stonith
High: PE: cl#5128 - Support maintenance mode for a single node
Low: PE: cl#5128 - Support maintenance mode for a single node (regression tests)
updated Ch-Stonith.txt with detailed topology example
Fix: PE: Delete the old resource state on every node whenever the resource type is changed

Do this even if the resource is not active on a node currently,
otherwise the next start op on the node will be injected into the old
lrm_resource entry.
Test: PE: Delete the old resource state on every node whenever the resource type is changed (update regression tests)
Merge pull request #286 from oallart/master

update Ch-Fencing in pacemaker_explained
Merge pull request #300 from gao-yan/delete-old-state

Fix: PE: Delete the old resource state on every node whenever the resource type is changed
Merge branch 'node-maintenance' of https://github.com/gao-yan/pacemaker
Refactor: crmd: Remove dead code
Fix: cluster: Correctly remove duplicate peer entries