Major view rework

I rework the whole view of the application:

- use FontAwesome for lot of icons and remove the use of image icons
- converted JavaScript files to CoffeeScript
- rework many CoffeeScript files, especially by changing event system
- improve use of structure elements such as <article>, <section> etc. in
  all view templates
- improve field structure (input controls with text content and field
  messages)
- optimize LESS/CSS files