Goes through all collections and attaches association helpers to them

meteor_add_association_helpers.js

var collections = [];

_.each(collections, function (collection) {
  var helpers = {};
  var fields = window[relation].simpleSchema().objectKeys();
  _.each(fields, function (field) {
    var key = field.replace(/Id$/, '');
    helpers[key] = function () {
      var entity = capitalize(key) + 's';
      return window[entity].findOne({_id: this[field]});
    };
  });
  window[relation].helpers(helpers);
});