udnisap

/* Extend the Underscore object with the following methods */

// Rate limit ensures a function is never called more than every [rate]ms
// Unlike underscore's _.throttle function, function calls are queued so that
//   requests are never lost and simply deferred until some other time
//
// Parameters
// * func - function to rate limit
// * rate - minimum time to wait between function calls
// * async - if async is true, we won't wait (rate) for the function to complete before queueing the next request