find_in_batches should use lexicographic select
Fix warning when scopes and limits are used
Ensure find_in_batches works with existing scopes
Simplify batch query
Merge pull request #150 from jordanbyron/find_in_batches

find_in_batches should use lexicographic order
Fix up nested attributes. #141.
Add helper parse method for cpk ids.
Merge branch 'master' of github.com:drnic/composite_primary_keys
Update history and version.
raise error on destroy when no pk is set
Fix bug where object == object returns false for new instances of a CPK model, even though
object.equal?(object) is true.
Instead of the generic message "Number of attr_names and values do not match", give specifics that
would aid in debugging, such as:
  Number of attr_names [:id_a, :id_b] and values ["a", "b", "t"] do not match
Merge pull request #159 from TylerRick/more_helpful_number_of_attr_names_error

Instead of the generic message "Number of attr_names and values do not match", give specifics that would aid in debugging
Merge pull request #158 from TylerRick/equality_of_equal_new_objects_fix

Fix bug where object == object returns false for new instances of a CPK model, even though object.equal?(object) is true.
Merge pull request #153 from adeven/master

raise error on destroy when no pk is set
Merge branch 'ar_4.0.x'

Conflicts:
	History.rdoc
	lib/composite_primary_keys/persistence.rb
Update to AR 4.0.0.
Bump version to 6.0.0
Up ruby version to 1.9.3 - rails 4.x won't run on earlier rubies.
Get rid of unneeded require.