code: function run(cmd) {
          return function (callback, options) {
              grunt.verbose.or.ok("Executing " + cmd);
              exec(cmd, options || {}, function (error, stdout, stderr) {
                  if (error) {
                      grunt.fatal("'" + cmd + "' failed with :" + stderr);
                  } else {
                      grunt.verbose.writeln("Result of " + cmd + ':\n' + stdout);
                      callback();
                  }
              });
          };
      }
docs: Helper function for shell commands (to be used by grunt.utils.async lib)