libcurl's WRITEFUNCTION is pretty fragile; if we destroy the CURL*
instance or even unregister it using curl_multi_remove_handle(),
libcurl will crash instantly.  But still we need to be able to handle
exceptions from inside the WRITEFUNCTION, and call
CurlResponseHandler::OnError(), which may destroy the whole thing.  As
a workaround, I use DeferredMonitor to postpone the OnError() call
into a stack frame which is allowed to destroy the request.

Let the caller decide what to do with the exception.

When the request is done, only unregister the CURL* handle, but do not
delete it yet - it may still be needed for CURLINFO_RESPONSE_CODE.

Convert assertion to runtime check.  This is useful because this is a
public method, and the caller has no chance to check if the object is
still registered.

Fixes a crash that can occur due to recursion from InvalidateSockets()
to ReadInfo() to CurlRequest callbacks.

Move code from SongFilter.cxx.

Changed AlsaMixerPlugin to use the get and set normalized functions from volume_mapping of alsa-utils/alsamixer
Changed volume_mapping set volume to be for all channels and not per channel
added volume_mapping files to Makefile.am

source:
http://git.alsa-project.org/?p=alsa-utils.git;a=blob_plain;f=alsamixer/volume_mapping.c;hb=HEAD
http://git.alsa-project.org/?p=alsa-utils.git;a=blob_plain;f=alsamixer/volume_mapping.h;hb=HEAD

This allows constructing an instance in any thread, and register it
inside the IOThread later.

Eliminate one unnecessary dependency for debug programs which don't
need the InputStream API.

Not used.  Force implementations to initialize out_audio_format.

Problems found by "make distcheck".

Fix for the problem where order with priorities gets out of whack in case it's
reordered by SetRandom() while another song is currently playing.
What happens is, if some song is already playing and you have set some
priorities before switching on the random mode, and then turn the mode on, the
original code swaps position of the first song in the order (i.e., the highest
priority song) with current, so that current is 0 (which it should be). The
problem is, the "original" first song then goes to the place "current" song was
after reordering, wherever that is, instead of going after the "current" song.
This patch fixes the issue.
Also the fix makes MoveOrder() public, because why shouldn't it be, anyway.  It
certainly makes more sense than just having SwapOrders() public for some
reason.
Signed-off-by: Eugene Baklanov <miltenfiremage@gmail.com>