need to http.resp.Body.Close() for a new connctn

otherwise we run out of connections and start getting nothing but these:

dial tcp: lookup [hostname]: no such host

https://code.google.com/p/go/source/detail?r=d4e1ec84876c0f5611ab86a03826da14b866efb2&name=release-branch.go1.1&path=/src/pkg/net/http/transport.go