Add verification socket close causes StopIteration
Add verification socket close causes StopIteration

This patch add a expositive test that closing connection
(fd and socket) causes StopIteration on reader at proxy server
on PUT object case.

And then, if the connection closed and proxy detects a lack of
data length, it will result in HTTPClientDisconnected.

The only reason why I leave test_client_disconnect as current
is Bill is now working for the change at

https://review.openstack.org/#/c/236007/

Change-Id: If68f752a2b0dd6cfad4d007ca5d155e6ffb378e5

williamthegrey/swift,aerwin3/swift,nadeemsyed/swift,openstack/swift,matthewoliver/swift,hurricanerix/swift,notmyname/swift,notmyname/swift,notmyname/swift,hurricanerix/swift,aerwin3/swift,tipabu/swift,smerritt/swift,mjwtom/swift,matthewoliver/swift,prashanthpai/swift,nadeemsyed/swift,openstack/swift,swiftstack/swift,nadeemsyed/swift,levythu/swift,tipabu/swift,prashanthpai/swift,swiftstack/swift,clayg/swift,redbo/swift,rackerlabs/swift,mjwtom/swift,bkolli/swift,smerritt/swift,matthewoliver/swift,clayg/swift,openstack/swift,smerritt/swift,larsbutler/swift,swiftstack/swift,smerritt/swift,rackerlabs/swift,daasbank/swift,larsbutler/swift,thiagodasilva/swift,williamthegrey/swift,psachin/swift,psachin/swift,tipabu/swift,clayg/swift,clayg/swift,redbo/swift,psachin/swift,tipabu/swift,psachin/swift,revoer/keystone-8.0.0,nadeemsyed/swift,matthewoliver/swift,hurricanerix/swift,hurricanerix/swift,daasbank/swift,thiagodasilva/swift,openstack/swift,revoer/keystone-8.0.0,levythu/swift,notmyname/swift,bkolli/swift