sbabook: typographic decisions and nitpickings (bulk list)

[cdlm]

• parts are numbered, it's not necessary
• in the TOC, the start of appendices is listed as a chapter instead of a part
• there is only the list of authors as appendix, it would have its place with the license colophon instead
• itemize lists have too much space before/after them
• code listings should probably wrap lines (issue Line breaks in code snippets #27)
• code listings should not show whitespace in strings, or in a quieter way (issue Explicit spaces in code snippets #26)
• long chapter titles should break in a proper place; this requires support from Pillar to place a hint in the markup
• the log listings in the Zinc chapter need to be set in a smaller font (issue Make some listings smaller #31)
• some itemized lists should really be descriptions (issue some itemized lists should really be descriptions #32)