[svn-r12815]

1) added a new parameter to the h5diff function diff_array that contains
the beginning position of the hyperslab, so that the total position in
the array is printed correctly when reading by hyperslabs.
2) added a new test to h5diff  that reads and diffs by hyperslabs. The
test reads a 1GB dataset, from which a 1KB hyperslab was written with
differences .
3) added the generation of 2 files to the generator program to test the
h5diff hyperslab read.
4) changed the h5diff binary pre-generated file names to be more
descriptive (e.g, instead of file1.h5, made it h5diff_basic1.h5)
5) changed the name of the h5repack options text file to info.h5repack

tools/h5diff/h5diff_common.c

@@ -285,7 +285,7 @@ int check_f_input( const char *str )
  */
 void usage(void)
 {
- printf("Usage: h5diff file1 file2 [OPTIONS] [obj1[obj2]] \n");
+ printf("usage: h5diff file1 file2 [OPTIONS] [obj1[obj2]] \n");
  printf("\n");
  printf("file1             File name of the first HDF5 file\n");
  printf("file2             File name of the second HDF5 file\n");