Delete UserRight instead of setting to USERRIGHT_NONE #1
Description
Currently, a UserRight can take 3 values: USERRIGHT_ALL (full access), USERRIGHT_ARTICLES (partial access, only to perms/a few factures endpoints) and USERRIGHT_NONE (no access - similar as no UserRight associated to the user). At the moment, when a user gets its rights switched to no access, the UserRight is kept in database. Given that there is no use of keeping USERRIGHT_NONE, we should bin this possible value - and delete this value instead in a similar situation.