Use Meteor Timers on server

When trying to use schedules on server is got can't find Fiber error.
Because later.js uses native setTimeout & clearTimeout.
According docs:
> Meteor uses global environment variables to keep track of things like the current request's user.
> To make sure these variables have the right values, you need to use Meteor.setTimeout instead
> of setTimeout and Meteor.setInterval instead of setInterval.

> These functions work just like their native JavaScript equivalents. If you call the native function,
> you'll get an error  stating that Meteor code must always run within a Fiber, and advising to use
> Meteor.bindEnvironment.

This patch makes native method clobbered with Meteor's versions in package closure.