hdf5_ep

[svn-r9829] Purpose: Clean up tests

Description:
    + replaced "goto error" with throw exceptions
    + properly cleanup dynamically allocated memory in failure cases,
        for in some cases, the execution continues on after the failures
        were reported.
    + added test utility class InvalidActionException for when an action
        should cause an exception but doesn't.

Platforms tested:
    SunOS 5.7 (arabica)
    Linux 2.4 (eirene)

    Note that there was an error due to the missing symbol H5E_LEN.  To
    be able to test my changes, I temporarily replaced H5E_LEN in c++/src
    with a constant as in the C tests, before the problem can be fixed.
    This value doesn't effect the C++ tests at all, at this time.