Show RecordInvalid in the documentation. References #10976 [kampers]

git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@8845 5ecf4fe2-1ee6-0310-87b1-e25e094e27de

activerecord/lib/active_record/validations.rb

 module ActiveRecord
   # Raised by save! and create! when the record is invalid.  Use the
-  # record method to retrieve the record which did not validate.
+  # +record+ method to retrieve the record which did not validate.
   #   begin
   #     complex_operation_that_calls_save!_internally
   #   rescue ActiveRecord::RecordInvalid => invalid
   #     puts invalid.record.errors
   #   end
-  class RecordInvalid < ActiveRecordError #:nodoc:
+  class RecordInvalid < ActiveRecordError
     attr_reader :record
     def initialize(record)
       @record = record