Create specific permissions for administer unmanaged file

Good and useful addition, working fine.

The MR in #2 and patch in #3 works fine. However, I have a use case where a role with the permission to "Delete any files" needs to have access to the "Unmanaged File List" to perform cleaning, but this role should NOT have access to the "Unmanaged File Settings".

The current patch removes access to both. Hence, we need more granular permissions to limit the access to the settings separately from the access to the list.

A new patch file with separate permissions.

IMO the unmanaged files list could be put in the content menu, but that's a separate issue if other people agree it would be better.

@daften I've applied your patch in #6, went to the permissions and granted a specific role the access to administer tasks only but seems like nothing has changed. That role and every role still have access to Administer unmanaged files and Administer unmanaged files settings. For this reason, I'm changing the status to Needs work.

Hi, I can't reproduce #7.

I have tested this with 3 different roles, one that has only the "administer unmanaged files", one that has only the "administer unmanaged files settings" and one that has none, and it works like expected. I had to clear cache after applying the patch, though.

@vegardjo Thank you for the cache clearing tip. I've made another test for the patch in #6 and after clearing the cache, I can confirm that it's working as expected. Moving this to RTBC!