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/window.cc

@@ -24,7 +24,7 @@ static LRESULT CALLBACK
 WndProc (HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
 {
 #ifndef NOSTRACE
-  _strace_wm (uMsg, wParam, lParam);
+  strace.wm (uMsg, wParam, lParam);
 #endif
   switch (uMsg)
     {