docs: function findById(schemaName, id) {
  	return new Promise(function(resolve, reject) {
  		var Model = db.mongoose.model(schemaName);
  
  		Model
  		.findById(id)
  		.exec(function(error, result) {
  			if (error) {
  				reqlog.error('internal server error', error);
  				reject(error);
  			} else {
  				resolve(result || 'notFound');
  			}
  		});
  	});
  }