Migrating to Ionic 2 RC 0 - CommonJS files

After migrating my app to Ionic 2 RC 0, I was able to typescript-compile my app, but the bundling failed with

bundle dev failed:  Module .../node_modules/log4javascript/log4javascript.js does not export getRootLogger 

Finally, after some googling, I found out, that I had to define the so-called custom named exports of log4javascript by myself:

1. Copy rollup.config.js from node_modules/@ionic/app-scripts/config into my own config directory.
2. Change my package.json according to the documentation:
   

   "config": {
     "ionic_rollup": "./config/rollup.config.js"
   },
   

3. Add configuration for commonjs plugin in rollup.config.js:
   

   plugins: [
     commonjs({
       include: [
         'node_modules/log4javascript/**',
       ],
       namedExports: {
         'node_modules/log4javascript/log4javascript.js': [
           'Appender', 'BrowserConsoleAppender', 'getLogger', 'getRootLogger', 'Level', 'LoggingEvent', 'logLog', 'PatternLayout'
         ]
       }
     }),
     ...
   ]
   

As you can see, I had to define every single thing I used from log4javascript. Not beautiful, but it works.