- Added icon-button UI code for the menubutton
- Upgrade to React 16 to allow non-standard attrs, such as `tooltiptext`
to support XUL tooltips
- Add i18n support for React UI elements
- Update tests for reactified tag selector
* Add a multi-process, gulp-based build system to support es6 features,
async/await, jsx and scss
* Add a package.json to support dependency management and allow starting
the build process via npm
* Replace embedded Bluebird library with npm-installed one
* Add react, react-dom and web-library
* Introduce a custom require() loader in include.js as well as a minimal
local require() implementation in various other places