Silence lots of warnings in lib/DtHelp.

* 64bit warnings
* Missing prototypes
* explicit parentheses / brackets

There's still some work to be done, but, as always, it's a start ...

cde/lib/DtHelp/FormatUtil.c

@@ -47,6 +47,7 @@
 /*
  * system includes
  */
+#include <ctype.h>
 #include <errno.h>
 #include <limits.h>
 #include <locale.h>