hdf5_der

[svn-r12803] Description:
    Finish new version of the I/O pipeline message, which is much smaller than
the previous version.  This version is used with the "use the latest version
of the format" flag.

    Closed several memory leaks/overruns (found with valgrind).

    Also, lots of compiler & formatting cleanups.

Tested on:
    Linux/32 2.6 (chicago)
    Linux/64 2.6 (chicago2)