[ADD] website_sale_browse_mode

[victor-champonnois]

internal task : https://gestion.coopiteasy.be/web#id=13307&action=475&active_id=478&model=project.task&view_type=form&menu_id=536

[remytms]

Great, nice feature and very simple. :)

Some points:

• Not sure if the name is clear enough. Perhaps something like website_sale_browse_only or website_sale_disable_shopping or website_sale_no_shopping, etc. But maybe it’s just me that did catch directly the meaning.
• I think that the case when the cart is not empty when the website shift to "browse only" should be take into account. In such case the user will be able to finish the payment of his/her cart. Maybe button on the cart view should be removed also.

[victor-champonnois]

@remytms
Thanks for the review

• I hid the cart icon. It does not prevent someone who just add "/cart" to the url to access their card but it's a quick fix.
• I renamed the module website_sale_browse_only