Whitespace in <pre> tags

[andrewgunn]

The strip plugin is too aggressive and targets innocent whitespace inside <pre> tags so I've updated strip.rb to exclude it:

# Replaces multiple newlines and whitespace 
# between them with one newline

module Jekyll
  class StripTag < Liquid::Block

    def render(context)
      super.gsub /(?<=\s)\n\s*\n(?![^<>]*<\/pre>)/, "\n"
    end

  end
end

Liquid::Template.register_tag('strip', Jekyll::StripTag)