Issue request over self.transport and return a Deferred which will fire with a Response instance or an error.
| Parameters | request | The object defining the parameters of the request to issue. (type: Request) | 
| Returns | The deferred may errback with RequestGenerationFailed if the request was not fully written to the transport due to a local error.  It may errback with RequestTransmissionFailed if it was not fully written to the transport due to a network error.  It may errback with ResponseFailed if the request was sent (not necessarily received) but some or all of the response was lost.  It may errback with RequestNotSent if it is not possible to send any more requests using this HTTP11ClientProtocol. (type: Deferred) |