There was multiple issues with `website_sequence` field, mostly coming from
commits during the last few years (eg 43c544f8a8) that tried to change the
`website_sequence` order to be the same as `sequence` but changing only part of
the code.
Other commits tried to restore that again by changing only some parts.
This commit does:
1. Originally, the `website_sequence` was supposed to be the opposite of
`sequence` field, the greater the first.
This commit ensure this is not the case anymore and it is used as the
regular `sequence` field.
2. `website_sequence` demo data was set between 4 and 1000, no need to use so
big differences. Plus, having a website_sequence set to 4 means the next
product would already have negative value.
3. Add `website_sequence` field in tree view in place of `sequence` for website
product view, and in debug mode on form view.
task-1960777
closesodoo/odoo#32593
Signed-off-by: Jérémy Kersten (jke) <jke@openerp.com>