Fix sync again. Moved sample alignment to basesink.

Fix sync again. Moved sample alignment to basesink.

Original commit message from CVS:
* ext/alsa/gstalsasink.c: (gst_alsasink_reset):
* gst-libs/gst/audio/gstaudiosink.c:
(gst_audioringbuffer_class_init), (audioringbuffer_thread_func),
(gst_audioringbuffer_stop):
* gst-libs/gst/audio/gstbaseaudiosink.c:
(gst_base_audio_sink_event), (gst_base_audio_sink_render),
(gst_base_audio_sink_change_state):
* gst-libs/gst/audio/gstbaseaudiosink.h:
* gst-libs/gst/audio/gstringbuffer.c: (gst_ring_buffer_stop),
(gst_ring_buffer_set_sample), (gst_ring_buffer_clear_all),
(gst_ring_buffer_commit), (gst_ring_buffer_read):
* gst-libs/gst/audio/gstringbuffer.h:
Fix sync again. Moved sample alignment to basesink.