After deleting a user using BULK delete and empty trash, it's impossible to create another user with the same username.

Steps:

1. Create a user (username: john, password: publish, email: john.doe@ez.no)
2. Delete this user using bulk delete in sub-items list
3. Go to the trash
4. Empty the trash
5. Go back to Users in Admin Panel
6. Create a new user using the same values as step 1

Actual result:

The user login 'john' is used by another user. You must enter a unique login.

ezuser database table still has the entry

Expected result:

Website administrators should be able to create a new user account using the same username. It should be solved like it is when user is removed from right sidebar menu (Delete button). User is not sent to trash, but removed permanently.