def parse(html)
  Nokogiri::HTML::DocumentFragment.parse(html).children.first
end

class String
  # Strip leading whitespace from each line that is the same as the
  # amount of whitespace on the first line of the string.
  # Leaves _additional_ indentation on later lines intact.
  # @see http://stackoverflow.com/q/3772864
  def unindent
    gsub /^#{self[/\A\s*/]}/, ''
  end
end