hdf5_ep

[svn-r6549] Purpose:
This is the first check-in message related to szip support at HDF5 1.6 release

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).

Solution:
In the configure.in and configure, I handled szip exactly the same as what zlib was built into
the HDF5.
Currently if you don't specify in the configure command line with:
./configure --with-szlib=/.....
Unless you put your szip library in your path,you will build the same HDF5 library like before.
Also, I only use static szip library to test with HDF5.

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: