Support named results in .all

[kentcdodds]

Like async's parallel. So it could go from this:

axios.all([getUserAccount(), getUserPermissions()])
    .then(axios.spread(function (acct, perms) {
        // Both requests are now complete
    }));

to this:

axios.all({ acct: getUserAccount(), perms: getUserPermissions()})
    .then(function (results) {
        // Both requests are now complete
        var acct = results.acct;
        var perms = results.perms;
    });

This makes adding new requests to all simpler because you don't have to keep track of the order of items. This is how I normally do stuff when I use async. Just thought I'd suggest it.

[mzabriskie]

I generally like the concept, however axios.all is just an alias for Promise.all. I don't want to deviate from the ES6 spec as it makes the API less predictable.