`TFPHTTPConnection`
pt		AllocateConnectionID
pt		ReadRequestContent
pt		UnknownHeader
pt		HandleRequestError
pt		HandleUnexpectedError
pt		SetupSocket
pt		SetBusy
pt		DoHandleRequest
pt		DoKeepConnectionIdle
pt		ReadRequestHeaders
pt		AllowNewRequest
pt		RequestPending
		Create
		Destroy
		HandleRequest