This is more robust, for example it allows using the Shine encoder
plugin instead of LAME.

Passing it by value is actually smaller (32 bit) than the rvalue
reference (64 bit pointer), and it ensures that the object is consumed
after the call returns, no matter how the methods are implemented.

Migrate callers to GetSocket().Read(), GetSocket.Write(), which is the
same.

Maybe this was once a required kludge for Windows, but it's not
anymore.

Fixes hanging playback with soxr resampler.

Closes #139, #141

Tremor decoder is unusable since commit 2ee43c40. Sound is distorted to
the point where it's nothing but noise.

The data from vorbis_synthesis_pcmout() needs to be scaled and
clipped for 16 bit sample size. For reference see
http://lists.xiph.org/pipermail/tremor/2010-April/001642.html and
http://lists.xiph.org/pipermail/vorbis/2006-October/026513.html.
Signed-off-by: Marcin Jurkowski <marcin1j@gmail.com>

Fixes the non-Linux build.

This loop was introduced in commit
24c1f463, but -EPIPE is not a possible
error condition for snd_pcm_hw_params().  This code does not appear to
make sense.  Problems with a wrong period_time should be caught before
that by snd_pcm_hw_params_set_period_time_near().

This commit removes the last "goto" in MPD!  Yay!