[latexrefman] more in sectioning

[Hefferon, Jim S.]

I moved material on \appendix and \frontmatter & \mainmatter & \backmatter to separate subsections.  

In part to provide an example for those, I added "Larger book template." Also added an article template.  

I also listed the sectioning parameters secnumdepth and tocdepth.  

Adjust wording of some other sections, such as Tables of Contents, to fit changes. Added examples and adjusted the wording of the main Sectioning section to fit the refactoring.

Jim

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