anchor.diff:  * 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
  
positive.code: 
  .Gem
  * Add step in `rake release` to set version back to *.dev
  * enable NOKOGIRI_USE_SYSTEM_LIBRARIES=1 to speed up nokogiri install (in .travis.yml, bundler in general)
  * Don't package sample documents (create separate folder in repo)
  
  //^
  .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
  
negative.code: 
  //^
  .Samples
  * add example of itemized dlist
  
  //^
  