Upgrade to UglifyJS2

Updated the build process to use UglifyJS 2 parameters (per issue #129). That is,  if you install it via `npm install uglifyjs`, that already is uglifyjs2.

The main difference for us is the way it encodes comments, i.e. requiring `@preserve` or `@license` according to JSDoc. Thus I updated the core comment according to JSDoc syntax and added 'et al.' to `@author`. I hope you don't mind, it just seemed polite.

The empty modified lines are in the diff because my editor automatically removes them (I told it too, makes life easier in the long run).