Add Go port of obfs-flash-server, like Python mki.v.
Add --port option to override bindaddr.
Add torrc-server for mkii.
Add README for building obfs-flash-server.
Merge branch 'master' of https://github.com/infinity0/obfs-flash
Merge branch 'master' of https://github.com/infinity0/obfs-flash
Add "BridgeRelay 1" to server torrc.

I guess this is needed to serve the directory; at least without it I got
this error after 20% on the client:

[info] connection_ap_process_end_not_open(): Edge got end (not a directory) before we're connected. Marking for close.
[info] internal circ (length 1): $0000000000000000000000000000000000000000(open)
[info] stream_end_reason_to_socks5_response(): Reason for ending (526) not recognized; sending generic socks error.
[info] connection_free_(): Freeing linked Socks connection [waiting for connect response] with 62 bytes on inbuf, 0 on outbuf.
[info] connection_dir_client_reached_eof(): 'fetch' response not all here, but we're at eof. Closing.
External listener.
Add internal listener.

The extended ORPort information will be wrong at this point, because
it's using the conn from the end of the proxy chain (on localhost), not
the original conn from the Internet.
Use a channel to pass the external conn information forward.
Merge remote-tracking branch 'infinity0/master'
Change the ORPort so it doesn't conflict with flashproxy-client.
Define ExtORPort in server torrc.
more robust handling of Deferreds
- fix some pylint warnings
implement a proper CLI and auto-select a free local port for flashproxy
- swallow errors in dummy Deferreds
Use syscall.SIGINT in place of os.Interrupt.

They are the same, but I want to also add handling for syscall.SIGTERM,
which doesn't have an analog in os.
Catch SIGTERM, and don't wait for a second signal.
Close listeners after first signal.