anchor.diff:  * CRITICAL: put e-book reader class on html instead of body
   * CRITICAL: we're dropping subsequent paragraphs of preamble when abstract is found...need to pass them through
   * CRITICAL: try to pull username from author email field; pull avatar from gravatar
  +* CRITICAL: make generated file name strategy configurable (source file vs id)
   * HIGH: cross references between chapters does not work (would it work if we used the smart cross reference syntax?)
   * HIGH: add full table of contents to nav.xhtml, but use hidden below first level (check if works in Kindle); respect toclevels
   * HIGH: if running on a single article, then the document id has a conflicting purpose
  
positive.code: * Don't package sample documents (create separate folder in repo)
  
  //^
  
  .Converter
  * CRITICAL: if document doesn't have doctitle, Untitled shows in epub2 TOC
  * CRITICAL: conversion missing in epub3 backend for embedded (AsciiDoc table cell?)
  
negative.code: * upgrade to kindlegen 2.9.6 (only works for Ruby >= 2.0.0)
  
  //^
  .Packager
  * HIGH: retain file name of original chapter file (otherwise, it can break interdoc xrefs)
  * HIGH: add NOTICE.adoc to e-book archive
  