[Users] Add user deletion

Request

User story

Me as an administrator, I want to be able to delete user accounts.

Design

Scenario

• Deleting a user would keep the node but set a new attribute deleted to True. This is to keep graph dependency.

Affected areas

• Users
• Launcher
• link.users

Tasks

• Redact request
• Design
• Add a right-click menu with "Edit" and "Delete" with a confirmation message.
• Add a footer button "Delete" with a confirmation message.
• Change footer layout to comply with UX rules (see the edition overlays in the Project Manager)
• Implement deletion (deleted attribute)
• Exclude deleted users from link.user getters (deleted=False parameter)
• Launcher: Forbid login with deleted user
• Launcher: Disconnect if deleted user