moved attribute transformation into generator

lib/connectors/query-generator.js

@@ -182,6 +182,14 @@ module.exports = (function() {
     */
     hashToWhereConditions: function(hash) {
       throwMethodUndefined('hashToWhereConditions')
+    },
+
+    /*
+      This method transforms an array of attribute hashes into equivalent
+      sql attribute definition.
+    */
+    attributesToSQL: function(attributes) {
+      throwMethodUndefined('attributesToSQL')
     }
   }