Properly clean up when connection fails before being opened.
Properly clean up when connection fails before being opened.

This can happen when we attempt to connect to a RegionServer, and we
buffer some RPCs to send once connected, but we never successfully
connect, because of a connection timeout.

Bug reported by Viral Bajaria.

mapr/asynchbase,tempbottle/asynchbase,manolama/asynchbase,mway08/asynchbase,StumbleUponArchive/asynchbase,angushe/asynchbase,angushe/asynchbase,SteamShon/asynchbase,nvoron23/asynchbase,manolama/asyncbigtable,tsuna/asynchbase,OpenTSDB/asyncbigtable,hhshuai/asynchbase,Connexity/asynchbase,yuzhu712/asynchbase,hhshuai/asynchbase,OpenTSDB/asynchbase,manolama/asynchbase,Connexity/asynchbase,StumbleUponArchive/asynchbase,tsuna/asynchbase,OpenTSDB/asynchbase,hzy001/asynchbase,tempbottle/asynchbase,nvoron23/asynchbase,pythian/asynchbase,yuzhu712/asynchbase,mapr/asynchbase,hzy001/asynchbase,adityakishore/asynchbase,adityakishore/asynchbase,mway08/asynchbase,SteamShon/asynchbase