IMSG_GET_FILE handles a path to a local file. fs now behaves like net, it sends a IMSG_GOT_CODE/META and optionally the file. This also includes a bit of refactoring: the send_file function was extracted from handle_get so it can be used in handle_get_file too.

file URIs have the two slashes after the protocol even when the hostname is not specified.

The computed request was discarded because we passed `path' to make_request. Passing NULL here makes the net proc use our computed request string. There was an error in the computed request btw, where \r\n were strcpy'd instead of cat'd.

initialize selector, address and port to "" to prevent a NUL deferencing on emit_line

Now that all the queues are correctly initialised, there's no need for that dance.