Throughout use strace class in place of individual functions and variables.

* cygwin.din: Eliminate _strace_wm.
* sigproc.cc (wait_sig): Temporarily add more debugging output.
* include/cygwin/version.h: Bump minor api to reflect export change.

winsup/cygwin/fhandler.cc

@@ -491,7 +491,7 @@ fhandler_base::read (void *in_ptr, size_t in_len)
   rpos_ += copied_chars;
 
 #ifndef NOSTRACE
-  if (strace_active)
+  if (strace.active)
     {
       char buf[16 * 6 + 1];
       char *p = buf;