Info about using wext386 and usmplay

if you are going to call usmplay from assembly code then look at the dos32
examples for most info, you compile the usmplay files in dos32 "mode"
(a parameter passed to tasm, look in the makefile in the dos32 subdir to
 usmplay)
after that you'll just need to call usmplay like in dos32.

if you want to rebuild the watcom libs with own settings then insert all
files from the \examples\usmlib\ directory in wext to some directory below
the "root" directory in usmplay (v1.1x) and remake it
