vchoi_fork

[svn-r4502] Purpose:
    'Bug fix'
Description:
    When testing the validity of zlib, the compress() function is
    used.  HDF5 actually requires a newer version of zlib which
    contains compress2().  Compress2 is tested in later part of
    the configure.  This caused redundent tests and confusion too.
Solution:
    Changed zlib test to look for compress2() instead.
    Older version of HDF4 libraries (e.g. 4.1r2) would fail this
    test correctly.  This eliminated the possibility of using an
    older version of HDF4 without using zlib compression in HDF5.
    But since we need newer version of hdp (with loops detection),
    the older version hdf4 is not old any more.
Remark: the compress2 test is not removed.  After this change
    proven working correctly for all platforms, the extra compress2
    test can be removed and source code must be updated too.
Platforms tested:
    modi4: tested with hdf4.1r2 and failed as expected.  Tested with
    newer hdf4 libraries and succeeded as expected.