Feature #2694: Improve ObjectCollection::from_xml_node

It could not parse xml with space between elements
(cherry picked from commit c026120a17659129e269ba25ce01ecdaea17ee01)
Bug #2839: Fsck now allows multiple system DS in the same cluster
Bug #2586: Remove formatting in fsck for Nokogiri docs. Contributed by Rolandas Naujikas
Bug #2586: Do not remove attibutes with space values