Log Message:
pianobar: Upgrade to 2017.08.30

pkgsrc changes:
 - switch to GitHub as the release source
 - set CFLAGS for NetBSD: _NETBSD_SOURCE, this works around a bug that
   strdup(3) was not included in the POSIX source namespace (fixed in
   NetBSD 8.0)
 - switch to ffmpeg 3.x

upstream changelog
==================
Release 2017.08.30

- Support binding to specific network interface, see config option bind_to
- New config option gain_mul softens effect of replay gain
- Replaced deprecated ffmpeg and json-c functions, bumps ffmpeg/libav version
  requirement
- Fix use-after-free
- Minor improvements to code and documentation

Release 2016.06.02

- Quit pianobar upon reception of two SIGINT
- Minor bugfixes