hdf5_ep

[svn-r8218] Purpose:
bug fix in H5Zshuffle.c
add more tests to h5repack that exposed the bug

Description:
when creating a dataset with the shuffle filter and duplicating it in a new dataset (file)
the call to H5Z_set_local_shuffle failed. this is because the value of cd_nelmts of the filter
structure is set to 1 (H5Z_SHUFFLE_TOTAL_NPARMS) when the original dataset is created, but when
the new dataset is created there is a checking instruction that fails if the value of
cd_nelmts is not 0 (its original value, H5Z_SHUFFLE_USER_NPARMS)

Solution:
just remove that check condition, since the value of cd_nelmts is not used anyway.
if we decide that the value of cd_nelmts is necessary, then the H5O_pline_copy function
must be changed to update this value (a different update for each filter)

Platforms tested:
linux
solaris
AIX

Misc. update: