Fix jekyll-assets get image dimensions
Fix jekyll-assets get image dimensions

Latest jekyll-assets update changed .width/height to .dimensions.width/.dimensions.height
nielsenramon/chalk,ulysses4ever/ulysses4ever.github.io,nielsenramon/chalk,ulysses4ever/ulysses4ever.github.io,nielsenramon/chalk,wyntre/chalk,wyntre/chalk,wyntre/chalk,giovannic/giovannic.github.com,nielsenramon/chalk,giovannic/giovannic.github.com,wyntre/chalk