- bugfix: stereo 16,24,32 bit code fails make test - 8 bit stereo, all mono ok
- revamp testing code. include 8, 16, 24, 32 bit, mono+stereo testing.
- check the above with and without inline
- check the above on big-endian platforms (so far just tested on little)
- re: 0x80000000 bug: can reproduce warning using 32 bit cc
- optimize Wav/Write as was done for Wav/Read - use _init_write_sub() first,
  then Inline::C
- use XS instead of Inline for portability if time