Microsoft and the open group both specify towupper and towlower as taking int

and returning int of some flavor.  Make this true of ours.

http://msdn2.microsoft.com/en-us/library/45119yx3(VS.80).aspx
http://opengroup.org/onlinepubs/007908799/xsh/towupper.html

svn path=/trunk/; revision=29073

reactos/lib/sdk/libcntpr/string/ctype.c

@@ -571,7 +571,7 @@ int toupper(int c)
 /*
  * @implemented
  */
-wchar_t towlower(wchar_t c)
+wint_t towlower(wint_t c)
 {
    if (iswctype (c, _UPPER))
        return (c - upalpha);
@@ -581,7 +581,7 @@ wchar_t towlower(wchar_t c)
 /*
  * @implemented
  */
-wchar_t towupper(wchar_t c)
+wint_t towupper(wint_t c)
 {
    if (iswctype (c, _LOWER))
       return (c + upalpha);