code: function normalize(loader, mods) {
  	var modNames = (mods && !Array.isArray(mods)) ? [mods] : mods;
  
  	return (modNames || []).map(function(moduleName) {
  		return !_.isString(moduleName) ?
  			Promise.resolve(moduleName) :
  			loader.normalize(moduleName);
  	});
  }
docs: Normalize module names
  @param {string|Array.<string>} mods A module name (or a list of them)
  @return {Array.<Promise.<string>>} An array of promises that resolved
  to normalized module names.