Design handlebars template

The aim of this pull request is to define a [handlebars.js][1] template for transcript output.

Part of my idea is that with a single template, we can put that template in multiple places on the site. Then, the workflow for redeploying style changes to the template is:

1. Tweak the template `.handlebars` file
2. (p)Recompile the template at the command line
3. Commit changes

[1]: http://www.handlebarsjs.com