hdf5_msb

[svn-r19623] Purpose:
    - Fix a bug in each of the metadata accumulator source and test code
Description:
    - In accum.c test file, switch dxpl_id used in H5F_accum_*
      function calls to H5P_DATASET_XFER_DEFAULT (instead of 
      H5AC_dxpl_id), to fix compilation on windows.
    - Changed boundary checking from <= to < when checking
      if a read from disk with overlapping dirty metadata in the 
      accumulator has the read ending such that it aligns exactly
      with the dirty accumulator (line 234 of H5Faccum.c).
Tested:
    - h5committested