Added tests for correct Compact behavior.
Added tests for all possible IDirectSound[8] creation modes with good
and bad arguments.
Split dsound.c and ds3d.c into separate files for IDirectSound and
IDirectSound8 interfaces and added code to not execute IDirectSound8
tests when run with a dsound.dll of version 7 or earlier.  We should
now be able to run these tests on a Windows system with DX7 or earlier
(untested).