hdf5_ep

[svn-r6550] Purpose:
To support szip compression in HDF5

Description:
szip compression support is required by NASA ESDIS. The compression algorithm
is a good compression algorithm for scientific data. In HDF5, we add another filter
function to make szip as a default compression package as we did for gzip(or zlib).

H5config.in needs to be regenerated by autoheader for SZIP flags.
Solution:
A new file called H5Zszip.c will be added in the Makefile.in
Flags like: HAVE_FILTER_SZIP    should be auto-generated by autoheader.

Platforms tested:
Since there are changes of configure.in and configure,I didn't use h5committest.                                    I tested with four platforms.
1) Linux 2.4 (eirene)
2) Solaris 2.7(arabica)
3) windows 2000(VS 6.0)
4) SGI IRIX6.5-64(modi4)
For test 1)-3), only basic C tests were done
For modi4 test, I tested 64-bit C,parallel and fortran.                                                         All tests passed, except a warning message from szip library when checksum is used in some order, which doesn't
cause any real problems.

Misc. update: