concatenated from:
https://cdn.jsdelivr.net/npm/underscore@1.13.1/underscore-umd.min.js
https://cdn.jsdelivr.net/npm/underscore.string@2.4.0/lib/underscore.string.min.js
https://cdn.jsdelivr.net/gh/uglyog/clientside-haml-js@release_5_4/lib/haml.min.js