using q.all and q.spread to straighten promises

straighten-promises.js

var q = require("q");

// v1
q.all([getUser(username1), getUser(username2)])
  .then(function(users) {
    makeFriends(users[0], users[1]);
  });

// v2 (even better)
q.all([fetchUser(username1), fetchUser(username2)])
  .spread(function(user1, user2) {
    makeFriends(user1, user2);
  });