Add user statuses and seed admin user

app/models/user.rb

@@ -3,4 +3,13 @@ class User < ApplicationRecord
   # :confirmable, :lockable, :timeoutable, :trackable and :omniauthable
   devise :database_authenticatable, :registerable,
          :recoverable, :rememberable, :validatable
+
+  # Statuses ordered by decreasing privileges
+  enum :status, {
+    admin: 1,       # admin level access
+    active: 2,      # read-write user level access
+    restricted: 3,  # read-only user level access
+    locked: 4,      # disallowed to sign in due to failed logins
+    disabled: 5     # administratively disallowed to sign in
+  }, default: :active
 end