Update Devise configuration after update to 3.5.1

The most notable change is the reduction of the maximum length of the
passwords. See Devise's CHANGELOG.md for more information:

https://github.com/plataformatec/devise/blob/master/CHANGELOG.md#351---2015-05-24

config/initializers/devise.rb

@@ -4,6 +4,8 @@ Devise.setup do |config|
   # The secret key used by Devise. Devise uses this key to generate
   # random tokens. Changing this key will render invalid all existing
   # confirmation, reset password and unlock tokens in the database.
+  # Devise will use the `secret_key_base` on Rails 4+ applications as its `secret_key`
+  # by default. You can change it below and use your own secret key.
   # config.secret_key = 'generate with `rake secret`'
 
   # ==> Mailer Configuration
@@ -61,7 +63,7 @@ Devise.setup do |config|
   # :database      = Support basic authentication with authentication key + password
   # config.http_authenticatable = false
 
-  # If http headers should be returned for AJAX requests. True by default.
+  # If 401 status code should be returned for AJAX requests. True by default.
   # config.http_authenticatable_on_xhr = true
 
   # The realm used in Http Basic Authentication. 'Application' by default.
@@ -128,6 +130,9 @@ Devise.setup do |config|
   # The time the user will be remembered without asking for credentials again.
   # config.remember_for = 2.weeks
 
+  # Invalidates all the remember me tokens when the user signs out.
+  config.expire_all_remember_me_on_sign_out = true
+
   # If true, extends the user's remember period when remembered via cookie.
   # config.extend_remember_period = false
 
@@ -137,7 +142,7 @@ Devise.setup do |config|
 
   # ==> Configuration for :validatable
   # Range for password length.
-  config.password_length = 8..128
+  config.password_length = 8..72
 
   # Email regex used to validate email formats. It simply asserts that
   # one (and only one) @ exists in the given string. This is mainly
@@ -176,7 +181,7 @@ Devise.setup do |config|
   # config.unlock_in = 1.hour
 
   # Warn on the last attempt before the account is locked.
-  # config.last_attempt_warning = false
+  # config.last_attempt_warning = true
 
   # ==> Configuration for :recoverable
   #
@@ -188,6 +193,10 @@ Devise.setup do |config|
   # change their passwords.
   config.reset_password_within = 6.hours
 
+  # When set to false, does not sign a user in automatically after their password is
+  # reset. Defaults to true, so a user is signed in automatically after a reset.
+  # config.sign_in_after_reset_password = true
+
   # ==> Configuration for :encryptable
   # Allow you to use another encryption algorithm besides bcrypt (default). You can use
   # :sha1, :sha512 or encryptors from others authentication tools as :clearance_sha1,
@@ -250,7 +259,7 @@ Devise.setup do |config|
   # The router that invoked `devise_for`, in the example above, would be:
   # config.router_name = :my_engine
   #
-  # When using omniauth, Devise cannot automatically set Omniauth path,
+  # When using OmniAuth, Devise cannot automatically set OmniAuth path,
   # so you need to do it manually. For the users scope, it would be:
   # config.omniauth_path_prefix = '/my_engine/users/auth'
 end