Would you consider a PR for cache resize?

[kevburnsjr]

I'm using golang-lru in an HTTP microcache.

I'd like to be able to specify my cache's size in bytes rather than length.
I have a pretty good idea of how I want to do it, but it will require resizing the cache length dynamically.
Would you consider a PR adding the following methods?

// Resize changes the cache size
func (c *Cache) Resize(size int) (evicted int) {
	c.lock.Lock()
	evicted = c.lru.Resize(size)
	c.lock.Unlock()
	return evicted
}

// Resize changes the cache size
func (c *LRU) Resize(size int) (evicted int) {
	diff := c.Len() - size
	if diff < 0 {
		diff = 0
	}
	for i:= 0; i < diff; i++ {
		c.removeOldest()
	}
	c.size = size
	return diff
}

[armon]

@kevburnsjr Sure, this seems like a valuable feature