Grunt githash grabber

grunt-githash.js

// use like <%= commitsha1 %>

grunt.registerTask('githash', function () {
  var done = this.async(),
      config;

  config = {
    cmd: 'git',
    args: ['rev-parse', '--verify', 'HEAD']
  };

  grunt.util.spawn(config, function (err, result) {
    grunt.config('commitsha1', result.stdout);
    grunt.log.ok('Setting `commitsha1` to ' + result.stdout);
    done();
  });
});