Admin: Allow cluster config options to be queried/modified/deleted. Broken in cs: 13c450735ba7
The cib_attrs.c code made assumptions about when dest_node was and was not set,
cs 13c450735ba7 broke those assumptions and as a result, crm_attribute could
not modify the contents of <crm_config>

Mercurial revision: a527349e8778cf6bc80346440759acea41dec30f