[IMP] Tour: add tour in web module; tour became available in backend.
[IMP] Tour: add tour in web module; tour became available in backend.
[FIX] Tour: error log fail; template of modal
[FIX] tour: check if the tour is already finish before check next step
[FIX] website: wrong cycling error message
[FIX] tour.js: clear localStorage before testing; add a better log title
[FIX] tour.js: don't throw error in tutorial mode; error with multi ajax request (change page, data...)
[FIX] tour.js: fickering of the popover in tutorial mode in backend
[FIX] tour.js: forgotten backdrop and orphan css
[IMP] tour.js: less flickering and clean code
merge upstream
Merge pull request #619 from odoo-dev/master-add-tour-backend-chm

[IMP] Tour: add tour in web module; tour became available in backend.