ActiveRecord::Extension to translate an Array of values into the approriate IN( … ) or NOT IN( … ) SQL.

Examples

 Model.find :all, :conditions=>{ :id => [ 1,2,3 ] }

 # the following three calls are equivalent
 Model.find :all, :conditions=>{ :id_ne => [ 4,5,6 ] }
 Model.find :all, :conditions=>{ :id_not => [ 4,5,6 ] }
 Model.find :all, :conditions=>{ :id_not_in => [ 4,5,6 ] }