http: respect `Connection: close' in HTTP/1.1 requests

http: respect `Connection: close' in HTTP/1.1 requests

HTTP/1.1 clients may wish to explicitly terminate the connection
upon reading the response.  While clients may specify HTTP/1.0
to force a disconnect, HTTP/1.0 lacked chunked encoding which
meant streaming responses of indeterminate length could be
silently truncated at the protocol level and undetectable in
cases of uncompressed plain-text.