Add pygments.css
ignore Gemfile.lock
Add Markdownizer.highlight_engine to support pygments.rb
FIXME: a safer way to eval code
Fix "defines this render_attribute method" test
Support customize rendered_attribute and multiple markdownize! columnst
Optimize #extract_highlights_from with cache
Integrate with Markdownizer.highlight_engine
support ``` style code extration; support pygments highlight, adjust language by Pygments::Lexer.find_by_extname
split specs in to diff files
support ```regexp for pygment
coderay和pygments兼容高亮