Eliminate audio clicks when loading a state or starting the next game.
Fix overflow in null audio driver on windows. Detect fast forward and
reset time counter.
Audio and record initializations are unified by providing helper functions for
opening the audio device and for setting the device parameters. The ioctl calls
are properly checked for errors and log an appropriate error message. The init
fails if the requested parameters are not supported by the device, i.e. 44.1kHz
16bit stereo for playback. This provides consistent behavior with all the other
audio backends.
Isaac Marovitz