anchor.diff:  * add title/subtitle delimiter into HTML and hide with CSS?
   * use less side padding in sidebar?
   * can we remove content wrapper in sidebar?
  -* sidebar heading not right in readmill...maybe nothing to worry about?
   * manually style ordered list numbers
   * reduce vertical margins around basic lists (partially addressed via "brief" class)
   * use float trick to fix line spacing for primary title like with the subtitle
   * better handling of title without subtitle, particularly HTML and CSS
   * add pink theme: http://designplus.co/en/designplus
  -* customize id of <item> elements in epub manifest?
  +* LOW: customize id of <item> elements in epub manifest?
   
   //^
   .Samples
  
positive.code: * CRITICAL: padding around code in formal listing blocks
  * CRITICAL: check style of level 5 and 6 headings (see Groovy docs)
  * CRITICAL: use CSS3 filter scheme that allows admonitions to appear correctly on Google Play Books
    - see if Google Play books supports JavaScript and epubReadingSystem (no, but adds its own class to body)
  * CRITICAL: use a following sibling selector for :first-line in abstract so it works when page is partitioned (e.g., in Google Play Books)
  * CRITICAL: add support for different numbering systems (lowergreek, etc)
  * CRITICAL: surround prose in <span> (e.g., simple <dd>) which is not nested in <p> or <div> so iBooks can change the font
  * HIGH: kindlegen no longer strips <header> elements, so we can drop our div wrapper hack
  * HIGH: don't set text color so light on monochrome devices (use media query to detect)
  * HIGH: make justify-text a class on body that can be controlled from AsciiDoc attribute (don't use word joiner in this case)
  * HIGH: image border option (or add drop shadow to screenshots in README)
  * HIGH: review the table border color
  * HIGH: style example block
  * HIGH: allow theme to be customized using stylesheet attribute
  * HIGH: move -webkit-hyphens: auto to epub3-css3-only inside @media not amzn-kf8? (if we decide to reenable)
  * MEDIUM: headshot has too much top margin when at top of page (not below section title)
  * namo pubtree is justifying preformatted blocks
  * support both jpg and png avatars
  * add docinfo support
  * add navigation links in meta, e.g.,
  
negative.code: 
  //^
  .Converter
  * CRITICAL: put e-book reader class on html instead of body
  * CRITICAL: surround prose in <span> (e.g., simple <dd>) which is not nested in <p> or <div> so iBooks can change the font
  * CRITICAL: don't drop subsequent paragraphs of preamble when abstract is found...need to pass them through
  * CRITICAL: if document doesn't have doctitle, Untitled shows in epub2 TOC (isn't this correct?)
  * 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: revisit the headshot image logic
  * HIGH: if running on a single article, then the document id has a conflicting purpose
  * HIGH: require spine option on include directive in order to create a chapter file (requires change in Asciidoctor)
  * HIGH: promote regexps to constants
  * HIGH: use more thorough image path resolution
  * HIGH: put shy marks after dashes to allow wrapping to occur in text justification
  * MEDIUM: add landmarks nav list to nav.xhtml; see https://github.com/IDPF/epub3-samples/blob/master/31/moby-dick-mo-xhtml/EPUB/toc.xhtml
  * MEDIUM: Kindle links to cover page when clicking on first chapter instead of first chapter page
  * MEDIUM: add icon & icon placement as attributes on btn macro
  * MEDIUM: move client sniffer JavaScript to file and read/include from converter
  * MEDIUM: use the dfn element for defining a definition of a term (not just term class); see https://developer.mozilla.org/en-US/docs/Web/HTML/Element/dfn
  * MEDIUM: source highlighting using Rouge (instead of Pygments)
  * MEDIUM: to remove text indent in mobi7, set width="0pt" (text-indent) on <p> tag; also set height="1em" (margin top)
  * MEDIUM: create back link in bibliography entry for each reference to it (currently only the first)
  * packager doesn't resolve include files in subdirectory totally correctly
  * implement checklists
  * quiet flag
  * document that to use kindlegen with Ruby 1.9.3, must use kindlegen 2.9.4 gem (or specify KINDLEGEN env var)
  
  //^
  .Packager
  