Don't show menu items in admin a user does not have permissions for
Is your feature request related to a problem? Please describe
When I add a Contributor to a podcast with limited access rights, it will still see all the available manu items in de admin area. When a login in Contributes clicks on a menu item it sees an 403 error page.
Describe the solution you'd like
- Hide the menu-items that a user don't has permissions to.
- If the main menu is empty, and a user is contributor to a single podcast, show the podcast menu.
- If the user is contributor to multiple podcasts: show a list of podcasts in the main menu.