class library: stop alive thread when quitting

Signed-off-by: Tim Blechmann <tim@klingt.org>
sclang: netAddrSend - print error message on failure

Signed-off-by: Tim Blechmann <tim@klingt.org>
sclang: TCP port - set remove address

Signed-off-by: Tim Blechmann <tim@klingt.org>
plugins: UIUGens - detach ui thread

as we don't have a deinit phase, we have to detach the ui thread. this
is leaking a thread!

Signed-off-by: Tim Blechmann <tim@klingt.org>
scsynth: fix cleanup of asio thread and driver lock

Signed-off-by: Tim Blechmann <tim@klingt.org>
scsynth: fix cleanup of TcpConnection & don't report EOF errors

Signed-off-by: Tim Blechmann <tim@klingt.org>