erp5_base: add constraint and action to make sure Employee Number is unique instead of manually setting

It is GPDR compliant, as no cookie is set

Use CSP to improve protection against XSS and improve user privacy.

No javascript is supposed to be executed on the error page.

Such web sites are meant for anonymous access only, to improve CDN usage.

Do not load any JS, because the gadget may crash too, as no erp5 field is rendered

Allow users to go to the homepage.

Prevent img to increase the page width.

Most listbox functionnalities are not supported by web_js_style for now, as no form is used by default

Their contents is already provided by the HTML page template.

Generate a hfeed in the HTML rendering.
https://indieweb.org/feed

Provide a RSS feed automatically.

Only generate the feed when rendering the web section in view mode.

Extract all feed informations in Javascript to allow styling it as a blog.

Add bt5 dependency to erp5_dms to retrieve the author title.

This allows called script to call script on them

If ignore_layout=1 is present in url query, static web section show the default view so user can modify properties

But for url like
https://erp5/web_site_module/static_web_site/web_page_module/111?ignore_layout:int=1&portal_skin=Slide...
static web section should do redirection instead of showing the default view

It's difficult to distinguish if it should do redirection or show the
default view for all kinds of url

To make it simple, if portal_skin is present in url query, static web
section will do redirection event if ignore_layout is present

alarm is disabled because of some issue since longtime ago
not good idea to enable it because a lot already handlered invoice will be generated

temporairy solution

1.use query factory instead of manually query
2.don't get all related object, use modification date to filter
3.synchronize only related service