[FIX] *: fix incorrect/unstable links

- Removed the doc version and absolute path from all user doc redirections.
- Made developer doc redirections use 13.0 instead of online, master or earlier version string.
- Fixed outdated links.
- Enforced the use of :doc:, :ref: and :download: directives for redirections.
- Replaced google drive/docs links by doc redirections.

accounting/localizations/france.rst

@@ -52,8 +52,8 @@ of conformity testifying that your software complies with the anti-fraud
 legislation. This certificate is granted by Odoo SA to Odoo Enterprise users 
 `here <https://www.odoo.com/my/contract/french-certification/>`_.
 If you use Odoo Community, you should 
-`upgrade to Odoo Enterprise <https://www.odoo.com/documentation/online/setup/enterprise.html>`_
-or contact your Odoo service provider. 
+`upgrade to Odoo Enterprise <https://www.odoo.com/documentation/13.0/setup/enterprise.html>`_
+or contact your Odoo service provider.
 
 In case of non-conformity, your company risks a fine of €7,500.
 

accounting/localizations/italy_IT.rst

@@ -25,8 +25,7 @@ elettronica sono i seguenti:
    di posta elettronica certificata sono fornite dal tuo fornitore o dal
    Ministero. Lo stesso server deve essere configurato come server che
    gestisce tutta la corrispondenza mail in Odoo, per saperne di più si
-   puo’ consultare la relativa
-   `guida <https://www.odoo.com/documentation/user/13.0/discuss/email_servers.html>`_.
+   puo’ consultare la relativa :doc:`guida <../../discuss/email_servers>`.
 
 -  Indirizzo PEC dell’ Azienda, tale indirizzo deve essere lo stesso
    registrato presso l’Agenzia delle Entrate per l’utilizzo dei servizi