Fix for not removing idle objects

Before my change, for-loop execute only once.
Let's simplify this part of condition:

(refreshIdle || (count - factory.min)) > toRemove.length

true || NUMBER > toRemove.length
true > toRemove.length

and if toRemove.length = 0
true > 0
true > false  -> true

but if toRemove.length = 1
true > 1
true > true -> false

And examples:
- before http://jsfiddle.net/mBbM7/
- after http://jsfiddle.net/nXWys/1/
Merge pull request #64 from PiotrWpl/patch-1

Fix for not removing idle objects