New changes made

Bug fixes
1)      Added SND_PCM_STOP_ROLLOVER;

2)      Using pp.start_mode SND_PCM_START_FULL to actually allow
buffering in io-audio to avoid potential jittery that is introduced by
either fragment size inconsistency or system jitter.

3)      In player thread used g_frame_size_p instead of
PREFERRED_FRAME_SIZE

4)      Using param.sched_priority=12;

5)      Using pp.buf.block.frags_max = 5;