Add titles to the rest of the files in active_model/validations/*

activemodel/lib/active_model/validations/exclusion.rb

 module ActiveModel
+
+  # == Active Model Exclusion Validator
   module Validations
     class ExclusionValidator < EachValidator
       def check_validity!

activemodel/lib/active_model/validations/format.rb

 module ActiveModel
+
+  # == Active Model Format Validator
   module Validations
     class FormatValidator < EachValidator
       def validate_each(record, attribute, value)

activemodel/lib/active_model/validations/inclusion.rb

 module ActiveModel
+
+  # == Active Model Inclusion Validator
   module Validations
     class InclusionValidator < EachValidator
       def check_validity!

activemodel/lib/active_model/validations/length.rb

 module ActiveModel
+
+  # == Active Model Length Validator
   module Validations
     class LengthValidator < EachValidator
       MESSAGES  = { :is => :wrong_length, :minimum => :too_short, :maximum => :too_long }.freeze

activemodel/lib/active_model/validations/numericality.rb

 module ActiveModel
+
+  # == Active Model Numericality Validator
   module Validations
     class NumericalityValidator < EachValidator
       CHECKS = { :greater_than => :>, :greater_than_or_equal_to => :>=,

activemodel/lib/active_model/validations/presence.rb

 require 'active_support/core_ext/object/blank'
 
 module ActiveModel
+
+  # == Active Model Presence Validator
   module Validations
     class PresenceValidator < EachValidator
       def validate(record)

activemodel/lib/active_model/validations/validates.rb

 require 'active_support/core_ext/hash/slice'
 
 module ActiveModel
+
+  # == Active Model validates method
   module Validations
     module ClassMethods
       # This method is a shortcut to all default validators and any custom

activemodel/lib/active_model/validations/with.rb

 module ActiveModel
+
+  # == Active Model validates_with method
   module Validations
     module HelperMethods
       private