Bugs:
  Find a way to make Sass comments work anywhere without breaking url(http://

Testing:
  Add Sass support for various utilities (benchmark, profile)

Documentation:
  ! Document Sass module
  Haml::Engine public method documentation could use work

Features:
  Sass should throw generic errors for undefined constants, not syntax errors
  Sass::Plugin should log errors
  Line numbers on Sass errors should be correct after empty lines
  There should be a way to represent options in-document
  Haml and Sass executables should return meaningful exit codes