handle servers closing encoded connections correctly

handle servers closing encoded connections correctly

Servers who advertise that they close the connection get the 'Closes'
encoding flag, but this conflicts with servers who response with a
transfer-encoding (e.g. encoding) as it is saved in the same flag.

We have a better flag for the keep-alive (or not) of the connection
anyway, so we check this instead of the encoding.

This is in practice not much of a problem as real servers we talk to are
HTTP1.1 servers (with keep-alive) and there isn't much point in doing
chunked encoding if you are going to close anyway, but our simple
testserver stumbles over this if pressed and its a bit cleaner, too.

Git-Dch: Ignore