h4h5tools

Add a test-suite for h4toh5 with -eos -nc4 option, and so on
  - create a test-suite for h4toh5 with -eos -nc4 option
    - AR_RnGd.hdf, MOD10A1.hdf are added (both have grid dataset)
  - modify codes that cause warnings regarding "const" modifier
  - make it compile with HDF5 1.6
  - remove "-q" from h5diff for lib test cases
  - add H5_USE_HDFEOS2 substitution rule for test driver

To build with HDF 1.8, configure option would be like:
  ./configure \
    --prefix=/mnt/scr1/cholee/h4h5tools \
    --with-hdf5=/mnt/hdf/cholee/hdf5/hdf5/ \
    --with-hdfeos2=/mnt/scr1/cholee/hdfeos2/ \
The test-suite for h4toh5 should print the following:
  Testing h4toh5 -e AR_RnGd.hdf AR_RnGd.h5                               PASSED
  Testing h4toh5 -e MOD10A1.hdf MOD10A1.h5                               PASSED

To build with HDF 1.6, configure option would be like:
  ./configure \
    --prefix=/mnt/scr1/cholee/h4h5tools \
    --with-hdf5=/mnt/hdf/cholee/hdf5_1_6/hdf5/ \
The test-suite for h4toh5 should skip the added two test cases
  Testing h4toh5 -e AR_RnGd.hdf AR_RnGd.h5                               -SKIP-
  Testing h4toh5 -e MOD10A1.hdf MOD10A1.h5                               -SKIP-

Still, H5_USE_16_API preprocessor definition should be used