vchoi_fork

Merging in latest from upstream (HDFFV/hdf5:refs/heads/develop)

* commit '9d6ba29a01079e0f81ffa530605d8cd830378f9c':
  Better segregate clean & dirty LRU lists so that they are only defined when the H5C_MAINTAIN_CLEAN_AND_DIRTY_LRU_LISTS macro is defined.