Improve production performance

The Angular documentation has some tips on how to improve app performance in production. Some of them could definitely be applied to the Channel Manager:

• disable debug data (when ConfigService.debug is false, i.e. when we're not running in Wicket development mode).
• disable comment and css class directives (I don't think we use them, but we'd have to double-check that).

AFAIK we already use strict DI mode, but let's check that too.