Incorrect sync order of related outbox items (sendAll)

[tomaszn]

When sending pending items, ones that depend on ids of other items should be postponed until what they refer to got their ids. I managed to get the batches of model names this way:

all_ready = [];
fresh = [];
do {
  new_ready = Object.values(app.config.pages).filter(function(page) {
    return page['list'] && !page.form.some(function(field) {
      return field['wq:ForeignKey'] && all_ready.indexOf(field['wq:ForeignKey']) == -1;
    });
  }).map(function(page) { return page['name']; });
  fresh = new_ready.filter(model => all_ready.indexOf(model) == -1);
  console.log('time to sync items from these models:', fresh);
  all_ready = new_ready;
} while (fresh.length);

After every item is synced, fields of relating items should be updated with a a persistent id obtained from the server.

[tomaszn]

Related to #85.

[sheppard]

I created a test case for this in 45cd0c3 and it seems to be working. Can you review and add more to the test, perhaps as part of #95?

I did find a bug while testing (see #102).

[sheppard]

This should be working pretty well now - see notes in #95.