[FIX] website tour: create a stub for bootstrap tour in automatic/test mode
[FIX] website tour: create a stub for bootstrap tour in automatic/test mode (need for full test and hide real bug for tour test)
[ADD] support for presized fields in website/image

also add presized field to attachments (automatically computed from datas)
[FIX] website: typo: message let the user think that he can change the mobile view while he cannot
[FIX] website: readability block with container css