hdf5_ep

[svn-r4905] Purpose:
    Regression tests
Description:
    Generic property classes derived from an existing class were not having
    the parent class's properties copied into the new class.

    Additionally, derived classes were not being detected correctly.

Solution:
    Added regression tests to verify that these fixes are working:
        Copied properties from parent class into derived class.

        Modified H5P_isa_class_real() to walk back up the chain of parent
        classes to proper detect derived classes.

Platforms tested:
    FreeBSD 4.5 (sleipnir)