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/calcurse.h

@@ -76,6 +76,7 @@
 #define gettext(String) (String)
 #define dgettext(String) (String)
 #define dcgettext(String) (String)
+#define ngettext(String1,String2,n) ((n) == 1 ? (String1) : (String2))
 #define bindtextdomain(String) (String)
 #define bind_textdomain_codeset(Domain,Codeset) (Codeset)
 #endif /* ENABLE_NLS */