headless_pianobar: Support command-line arguments

See issue #383.
waitress: Move testcases to separate file

Now the test-enabled waitress.o does not conflict with pianobar’s
waitress.o any more, thus running `make test` without `make clean` works
fine.
Prepare for release 2013.09.15
Back to -dev
Port to OpenBSD

This really just tells the makefile how to call the compiler
on OpenBSD. You'll also want the following packages:
  json
  libmad
  libao
  faad
  gnutls