根据
underscore documentation：
throttle_.throttle(function,wait)
Creates and returns a new,
throttled version of the passed function,that,when invoked
repeatedly,will only actually call the original function at most once
per every wait milliseconds. Useful for rate-limiting events that
occur faster than you can keep up with.
这是什么意思有用的速率限制事件发生速度比你可以跟上.
这个函数等同于setTimeout和一个调用自身的函数？
有人可以在jsfiddle上为我提供一些例子吗？
