Remove iteration of config args

Fixes #154 - args should only contain the property name at that point,
not loop over it.

lib/validations.js

@@ -641,13 +641,13 @@ function configure(cls, validation, args, opts) {
     conf.customValidator = args.pop();
   }
   conf.validation = validation;
-  args.forEach(function (attr) {
+  var attr = args[0];
+  if (typeof attr === 'string') {
     var validation = extend({}, conf);
     validation.options = opts || {};
     cls.validations[attr] = cls.validations[attr] || [];
     cls.validations[attr].push(validation);
-  });
-  
+  }
 }
 
 function Errors() {