HADOOP-9910. proxy server start and stop documentation wrong. Contributed by Andre Kelpe. (harsh)

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HADOOP-9906. Move HAZKUtil to o.a.h.util.ZKUtil and make inner-classes public (Karthik Kambatla via Sandy Ryza)

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Adding and removing files missed for HADOOP-9906

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YARN-1101. Active nodes can be decremented below 0 (Robert Parker via tgraves)

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