Implement handling of chunked "Transfer-Encoding".

Hi Satoshi,

this is a small patch which implements the handling of HTTP responses which are encoded in chunks. Net::UPnP does not work with SONOS devices (multi room audio distribution devices) since they are replying in the chunked encoding style. My merge request implements the missing decoding logic. This enables Net::UPnP to handle the device and service descriptions correctly.


HTH,
Thomas