[FIX] web_kanban: fixed issues when having no column to display in kanban
view.
[IMP] ir_ui_view: pep8 + log catched exception when view_id cannot be found.
[IMP] ir_http: don't handle exception in dev mode but use the werkzeug debugger except if cause has been already identified (website Qweb)
[IMP] remove instant click
[IMP] sale_stock: better inherit

Better inherit of tree view of sale order line with position="attributes"
instead of postion="replace"
Fixes #3664, #3726
[FIX] im_livechat : do not crash if not Referer url in the header of the request.