Support these PCM formats natively, instead of letting libsndfile
convert everything to 32 bit.

Prepare for other sample formats.

Workaround for assertion failure in PrintUniqueTag().

Break the mainloop and terminate run call.

The second time init was called, http_200_aliases pointed to a freed pointer
and leaded to a SEGFAULT.

That attribute was uninitialized before, which could crash
libavformat.

See Debian bug 760669

See code comment.  Fixes assertion failure in
decoder_command_finished().

Log call was added to the wrong branch.

Fixes regression by commit ca1a1149

Eliminate the duplicate pa_operation_get_state() call.

Casting std::numeric_limits<unsigned>::max() to "long" leads to an
overflow if sizeof(unsigned)==sizeof(long), and the result will be -1.

This happens on some 32 bit architectures, for example ARM and WIN32.

Workaround: use std::numeric_limits<int>::max(), which is the largest
signed integer.  Since sizeof(long)>=sizeof(int), this will never
overflow.

Fixes Mantis ticket 0004080.

Since BroadcastError() calls BroadcastMountError(), there's no need to
check mount_finished here.