code: function matchesWildcard (subscriptions, channel) {
      var i;
      var subs = Object.keys(subscriptions);
      for (i=0; i < subs.length; i++) {
          if (matchesFilter(subs[i], channel)) {
              return subs[i];
          }
      }
      return undefined;
  }
docs: Helper function that tries to match a channel with each subscription it returns undefined if no match is found