h5repack revision:
1. added a new test due to the introduction of H5Ocopy in the copy of objects (compressed dataset with references, that still must go a second sweep of the file to be regenerated).
2. Moved all the source files from the h5repack test program to a new file h5repacktst.c and removed the old ones (testh5repack*.c).
3. Renamed the binary files from test*.h5 to h5repack*.h5 for easy reference.
4. Modified the shell script to use variables for file names instead of hard coded names
