added config.active_record.whitelist_attributes which creates an empty whitelist of attributes available for mass assignment for all models in your app

updated the security guide on the updated mass-assignment security scopes addition, and assign_attributes in AR

Added assign_attributes to Active Record which accepts a mass-assignment security scope using the :as option, while also allowing mass-assignment security to be bypassed using :with_protected

AM mass assignment security attr_accessible and attr_protected now allow for scopes using :as => scope eg.
    
    attr_accessible :name
    attr_accessible :name, :admin, :as => :admin

Conflicts:
	activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb

fetch result row arrays from pg in C and return early if there are no money or binary columns. ❤

We cant use assert_block because its buggy in MiniTest and wont actually show you the failure message you provide -- instead you just always get a "Expected block to return true"

The #substitute_at gets an ActiveRecord::ConnectionAdapters::Column in #insert to match replacement in #exec_query.