Merge pull request #686 from shakedown/bug/1.5.x/paging-order-by-strings

Bug: validate order-by against strings for facts/fact-names/nodes
(PE-1450) Query paging tests for events
(PE-1450) Query paging tests for reports
(PE-1450) Query paging tests for event-counts
(PE-1450) Query paging test-placeholder for facts
(PE-1450) Query paging tests for nodes