ObjectMemory: reloadKnownObjectClasses()

It is now possible, to trigger the reloading of the object classes in the ObjectMemory.

The corresponding client code would look something like this:

// Trigger reloading of object classes in object memory
{
    auto objectMemoryPrx = armarx::armem::server::ObjectMemoryInterfacePrx::checkedCast(
        objectPoseStoragePrx_);
    ARMARX_CHECK_NOT_NULL(objectMemoryPrx);

    ARMARX_INFO << "Reloading known object classes to make new class available";
    objectMemoryPrx->reloadKnownObjectClasses();
}