.. and not the stack buffer.  This made the AllocatedString destructor
crash.

Closes #52

Was broken by commit 8a86460b

Closes #87

Addresses #82.

Previously, the ffmpeg decoder only checked for the "generic"
MusicBrainz metadata keys used in other metadata container formats.

This commit is similar to 788e3b31,
and removes more "pure" attributes which were placed on functions that
could throw exceptions, which is illegal according to clang's
understanding of the attribute (but not according to GCC's).  GitHub
issue #58 was most likely about StorageDirectoryReader::GetInfo() and
Storage::GetInfo(), which still had "pure" attributes.

Closes #58

Add ffmpeg decoder support for *.adx files (Sega game console)

Closes #60

Patch from
 https://svnweb.freebsd.org/ports/head/audio/musicpd/files/patch-src_system_ByteOrder.hxx?revision=441921&view=co
(with a tiny modification)

Closes #59

Fixes build failure on OS X, closes #44.  With the other plugins,
that's not critical, because those use the AudioOutputWrapper, which
hides this problem.

Closes #34

The "pure" and "const" attributes are not so well-defined, and a
recent clang version implements an optimization which pushes the
definition's boundary beyond what I believed it was.  clang now
assumes that functions declared "pure" cannot throw exceptions, even
if they lack the "noexcept" specification.

When compiled with this new clang version, MPD will crash randomly if
an exception happens to get thrown by such as "pure" function
(https://github.com/MusicPlayerDaemon/MPD/issues/41).

This commit removes all such misplaced "pure" and "const" attributes,
closing #41.

An ino_t is usually a 64 bit integer, and some file systems (such as
Linux's kernel NFS client) really uses the upper 32 bit.  This can
lead to false positives in the directory loop detection in
FindAncestorLoop().  Increasing these two attributes (in
StorageFileInfo and Directory) to 64 bit adds little overhead, but
makes the check a lot safer.

The TAG_MODIFIED handler (i.e. playlist::TagModified()) works only if
the modified song is the current song - something that is not updated
until SYNC_WITH_PLAYER is finished.  This fixes tag updates right
after a new song is started.

https://bugs.musicpd.org/view.php?id=4665

This repairs the damage to commit 74dbaade done by commit
b3f5b493

https://bugs.musicpd.org/view.php?id=4656 describes a crash due to
division by zero because frame.samples==0.  This should never happen,
but apparently can happen after seeking.  The best we can do is to
just ignore this frame.

Fixes another buffer overflow: if the stream has a very long title or
URL, resulting in a metadata string of more than 2 kB, icy_string[0]
is a negative value, which gets casted to size_t - ouch!

 https://bugs.musicpd.org/view.php?id=4652

Fixes potential crash bug.

The libsidplayfp fork has merged libsidutils into the main library.
The libsidutils we used to link with was part of the original
libsidplay project.

When rpc_reconnect_requeue() gets called from inside nfs_service(),
the NfsInputStream can stall completely because the old socket has
been unregistered from epoll automatically, but the new one has never
been registered.  Therefore, nfs_service() will never be called again.

This kludge attempts to detect this condition by checking
nfs_which_events()==POLLOUT.

https://bugs.musicpd.org/view.php?id=4081

Same as in commit e02d8ad8, but this time for the sndio plugin
which can be emulated by libroar.

GCC 4.9 has incomplete C++14 support.  Specifically, it doesn't allow
switch/case in "constexpr" functions.