Fix compilation with NLS disabled

* src/utils.c: Only call setlocale() if NLS is enabled.
* src/calcurse.h: Define a fallback macro ngettext() if NLS is disabled.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

src/utils.c

@@ -383,15 +383,19 @@ char *date_sec2date_str(long sec, const char *datefmt)
 /* Generic function to format date. */
 void date_sec2date_fmt(long sec, const char *fmt, char *datef)
 {
+#if ENABLE_NLS
   /* TODO: Find a better way to deal with localization and strftime(). */
   char *locale_old = mem_strdup (setlocale (LC_ALL, NULL));
   setlocale (LC_ALL, "C");
+#endif
 
   struct tm *lt = localtime((time_t *)&sec);
   strftime(datef, BUFSIZ, fmt, lt);
 
+#if ENABLE_NLS
   setlocale (LC_ALL, locale_old);
   mem_free (locale_old);
+#endif
 }
 
 /*