Using Angular with webpack makes the production build a breeze. Simply alter your webpack configuration at runtime based on an environment variable, and you're good to go.
Did you try what I recommended in my response to your other comment? https://egghead.io/forums/lesson-discussion/topics/angular-with-webpack-requiring-templates#post-3602
You'll see this message when UglifyJS can't parse your code. This particular message makes me think that you're not transpiling ES6 modules (
default is a keyword for ES6 modules). Make sure that you're transpiling modules with Babel (or Webpack 2 beta which understands and transpiles ES6 modules).