Ensure all calls that could deplete the _queue and _pending are in a state lock first.
Ensure all calls that could deplete the _queue and _pending are in a state lock first.

bsanders/kazoo,pombredanne/kazoo,harlowja/kazoo,python-zk/kazoo,rgs1/kazoo,harlowja/kazoo,Asana/kazoo,pombredanne/kazoo,kormat/kazoo,rackerlabs/kazoo,kormat/kazoo,jacksontj/kazoo,rgs1/kazoo,rockerbox/kazoo,rockerbox/kazoo,tempbottle/kazoo,bsanders/kazoo,jacksontj/kazoo,tempbottle/kazoo,rackerlabs/kazoo,max0d41/kazoo,AlexanderplUs/kazoo,AlexanderplUs/kazoo,max0d41/kazoo,python-zk/kazoo