[REFACTOR]: New architecture of catalog service

[jlabatut]

Description

According to #8, we need to update the catalog service in order to be v3 compliant. This involves :

• Remove cursus endpoints, schema, models.
• Remove tags, passwords, user database table
• Remove draft, rename name to title
• Rename modules to sections
• Add order to elements inside sections
• Remove all unused fields for videos and quizzes (just keep the ID and the type)

Also, we need to write the migration script in the SAME PR.

[jlabatut]

Time estimated : 2 m/d