extra port nnnn, nts port nnnn

[Hal Murray]

I just pushed code that optionally listens on a second port.

The NTS-KE server will tell the client to use that port.
Requests going out will be from the new port.

The idea is to bypass ISP filtering on port 123.

Testing encouraged.  I've been testing with
  nts port 8123

Be sure to let traffic on that port through your firewall.

I'm pretty sure I didn't break anything if you don't use this feature.

It hasn't been tested with ethernets that get unplugged and plugged back in or 
wifi that comes and goes or laptops going to sleep...

We should tweak the code so that server foo.example.com:8123 does the obvious 
thing.

-- 
These are my opinions.  I hate spam.