* The plugin itself is GPLv2+, as specified in README.md.
* Bundled JavaScript libraries (these all reside in htdocs/):
  - JQuery-UI is dual licensed, GPLv2 and MIT.
  - backbone.js and backbone-min.js are licensed MIT.
  - jquery.ba-throttle-debounce.min.js is dual licensed, GPLv2 and MIT.
  - json2.js is licensed Public Domain.
  - underscore-min.js is licensed MIT.
