* Generate Reader and Writer methods which cache attribute values in hashes. This is to avoid repeatedly parsing the same date or integer columns.
* Move the attribute related methods out to attribute_methods.rb to de-clutter base.rb
* Change exception raised when users use find with :select then try to access a skipped column. Plugins could override missing_attribute() to lazily load the columns.
* Move method definition to the class, instead of the instance
* Always generate the readers, writers and predicate methods.
git-svn-id: http://svn-commit.rubyonrails.org/rails/trunk@7315 5ecf4fe2-1ee6-0310-87b1-e25e094e27de