Fix PK key

Author: mceachen

spec/db/schema.rb

@@ -19,7 +19,7 @@ def force_add_index(table_name, columns, options = {})
     t.datetime "updated_at"
   end
 
-  force_add_index "nodes", [:id], :name => "node_id", :unique => true
+  force_add_index "nodes", [:uuid], :name => "node_id", :unique => true
 
   create_table "node_hierarchies", :id => false, :force => true do |t|
     t.string "ancestor_id", :null => false