hdf5_msb

[svn-r10017] Purpose:
bug fix/new feature.

Description:
(committing changes made by Leon.)
ph5diff now is a real program by itself.  It has its
own main (ph5diff_main.c).
Codes common to h5diff and ph5diff are in h5diff_common.c.

Removed the hack that hide failures from testh5diff.sh.

Platforms tested:
heping(serial, pp), sol (pp), copper(pp).

Misc. update: