Combine sections on compound documents (bundling)

[MikeRalphson]

As briefly discussed with @Relequestual, the spec. has two locations where it talks about and defines the process for bundling compound documents: s.9.3 and Appendix B.s.1

Even if these sections do effectively express the same rules, having two places to understand and compare within the spec. seems suboptimal. Could they possibly be merged going forwards?

[jdesrosiers]

I think section 9.3 should have replaced Appendix B. I think Appendix B can just be removed.