cli: add option to server streams externally without a player

[danielkza]

Add an option to the CLI name --player-external-http, to start an HTTP
server like --player-continuous-http, but without starting a
corresponding player, and streaming to all available interfaces instead
of just the loopback.

This can be useful to stream to devices like smartphones or streaming
boxes, while making use of the better compatibility and performance of
livestreamer.

An accompanying --player-external-http-port option was added to allow
people behind firewalls to add their exceptions only once.

When starting livestreamer in this mode, URLs for the server will be
printed instead of a player being started. Those are detected based
on the IPv4 addresses returned by calling
socket.getaddrinfo(socket.gethostname(), ...), which will work for sure
on UNIX platforms, and should on Windows as well (actual testing
pending), in addition to 127.0.0.1.

[danielkza]

It seems there's something wrong with Travis, it's failing to fetch packages before even starting the tests. Is an apt-get update missing?

[chrippa]

Thanks!

[danielkza]

Cool, did you get to test it on Windows and/or OS X?

[danielkza]

It seems I broke player-continuous-http, I'll push a new commit fixing it (sorry!).

[chrippa]

Cool, did you get to test it on Windows and/or OS X?

No, I don't have access to any machines with those OSes currently. But the socket API should work fine on those OSes.

It seems I broke player-continuous-http, I'll push a new commit fixing it (sorry!).

No problem, I've already got a fix in my local repo that i'll push in a minute.

[danielkza]

I pushed a fix as well, it just corrected the default value for the port parameter. I also updated the docstrings for the HTTP functions a bit to match the changes.

edit: Apparently there is no way to update merged pull requests. Annoying.