old_contents: module.exports = function (grunt) {
  
  	grunt.initConfig({
  
  	});
  
  
  
  };
new_contents: module.exports = function (grunt) {
  
  	grunt.initConfig({
  
  		meta: {
  			banner: '// ' + grunt.file.read('LICENSE').split("\n")[0]
  		},
  
  		coffee: {
  			compile: {
  				files: {
  					'lib/x18n.js': ['lib/observable.coffee', 'lib/x18n.coffee'],
  					'spec/spec.js': 'spec/spec.coffee'
  				}
  			}
  		}
  
  	});
  
  	grunt.loadNpmTasks('grunt-contrib-coffee');
  
  };
subject: add coffee task