Update readme: bundle install instructions, kramdown not maruku, links to Mou
Point to jekyll install docs rather than listing instructions here.
Install gems into vendor/bundle. Gitignore vendor/bundle, and tell jekyll not to include it in the site.
Merge pull request #393 from benshine/update-readme-bundler-kramdown-screenshot

Update readme: bundle install instructions, kramdown not maruku, links to Mou