Fixed #move_above by explicitly referencing self.parent rather than parent .
Fixed #move_above by explicitly referencing self.parent rather than parent .

devilcoders/mongoid-tree,gurix/mongoid-tree,macdiesel/mongoid-tree,zenjoy/mongoid-tree,radin-reth/mongoid-tree,benedikt/mongoid-tree,epogue/mongoid-tree,travis-repos/mongoid-tree