attempt to emulate the missing support for mongo array upserts

array-upsert.js

// mongo array upsert
mongo('settings').update({'authorizations._id': {$ne: app._id}}, {$push: {'authorizations': app}}, {safe: true, 'new': true}, function(err, newSettings){
	if (err) {
		return callback(err);
	}
	if (!newSettings) {
		return mongo('settings').update({'authorizations._id': app._id}, {$set: {'authorizations.$': app}}, {safe: true}, callback);
	}
	callback();
});