Add missing task `grunt test`

This command for test is documented in
[README.md#from-the-cli](https://github.com/emberjs/data#from-the-cli).
var matchdep = require('matchdep');
module.exports = function(grunt){

  matchdep.filterDev('grunt-*').forEach(grunt.loadNpmTasks);
  grunt.loadTasks('tasks');
  var config = require('load-grunt-config')(grunt, {
    configPath: __dirname + '/tasks/options',
    init: false
  });

  config.pkg = require('./package');
  config.env = process.env;

  grunt.initConfig(config);

  grunt.registerTask('buildPackages', [
    'clean',
    'transpile:amd',
    'concat:globals',
    'browser:dist',
    'jshint'
  ]);

  grunt.registerTask('buildTests', ['concat:tests']);
  grunt.registerTask('dev', [ 'connect', 'watch' ]);
  grunt.registerTask('test', ['buildPackages', 'buildTests', 'connect', 'qunit', 'uglify']);
  grunt.registerTask('default', ['test']);
};

var matchdep = require('matchdep');
module.exports = function(grunt){

  matchdep.filterDev('grunt-*').forEach(grunt.loadNpmTasks);
  grunt.loadTasks('tasks');
  var config = require('load-grunt-config')(grunt, {
    configPath: __dirname + '/tasks/options',
    init: false
  });

  config.pkg = require('./package');
  config.env = process.env;

  grunt.initConfig(config);

  grunt.registerTask('buildPackages', [
    'clean',
    'transpile:amd',
    'concat:globals',
    'browser:dist',
    'jshint'
  ]);

  grunt.registerTask('buildTests', ['concat:tests']);
  grunt.registerTask('dev', [ 'connect', 'watch' ]);
  grunt.registerTask('default', ['buildPackages', 'buildTests', 'connect', 'qunit', 'uglify']);
};
