Prior to this commit:
* All employees were treated the same way regarding the contractual point of vue.
From this commit on:
* Three employee types will be created:
- Employee, which is supposed to be under contract
- Student & Contractor which are both not supposed to have an employee contract (but are still use the employee as working for the company)
* Employee view and Contract History will take this consideration into account.
closesodoo/odoo#64931
Taskid: 2446000
Signed-off-by: Yannick Tivisse (yti) <yti@odoo.com>