Big & Small display modes, with Retina support

[TheophileBarbin]

Includes:

• All paddings, pixels sizes, boxes etc. change
• All font sizes change
• All icons in two other formats (Big & Small)
• Retina displays support

[armandgrillet]

We can nom use the functions set[Min|Max][Width|Height]() to enhance the user experience when a user changes the display mode, I need to know:

• What will be the smallest screen width to display the option "big".
• What will be the min-width setted depending on each option (small/normal/big).

[TheophileBarbin]

Won't fix, not enough time left.

[armandgrillet]

Milestone changed but I keep it open.