Add README section on combining assets
Add README section on combining assets

This is in response to jekyll/jekyll-assets#241: currently, it is not documented
how to combine JavaScript files into one script.

This adds a new section to the README, explaining how users can combine
SASS and JS files.
mattbeedle/jekyll-assets,mattbeedle/jekyll-assets,mattbeedle/jekyll-assets,jeremy/jekyll-assets,jeremy/jekyll-assets,mattbeedle/jekyll-assets,jekyll/jekyll-assets,jeremy/jekyll-assets,jeremy/jekyll-assets,jekyll-assets/jekyll-assets,jekyll-assets/jekyll-assets,jekyll-assets/jekyll-assets,jekyll/jekyll-assets,jekyll/jekyll-assets,jekyll/jekyll-assets