updated for version 7.3.446
Problem:    Win32: External commands with special characters don't work.
Solution:   Add the 'shellxescape' option.
diff --git a/src/option.h b/src/option.h
index 21c2753..9dd9387 100644
--- a/src/option.h
+++ b/src/option.h
@@ -712,6 +712,7 @@
 #endif
 EXTERN char_u	*p_shq;		/* 'shellquote' */
 EXTERN char_u	*p_sxq;		/* 'shellxquote' */
+EXTERN char_u	*p_sxe;		/* 'shellxescape' */
 EXTERN char_u	*p_srr;		/* 'shellredir' */
 #ifdef AMIGA
 EXTERN long	p_st;		/* 'shelltype' */