Remove invalid custom ngettext() macro

This patch removes all custom gettext macro definitions. There are multiple
issues with these macros:

- They are redundant: gettext functions are already declared in <libintl.h>
- The implementations of the ngettext macros are invalid
- If an Xfce GUI app or plugin accidentally uses any of the gettext macros
  defined in xfce-i18n.h, then it completely disables localication in the
  app or plugin

The file <libintl.h> containing the declaration of gettext() has been
included by both <gi18n.h> and <gi18n-lib.h> since year 2008 (at least).

The removal also resolves the following warning messages:

GISCAN Libxfce4util-1.0.gir
xfce-i18n.h:61: Warning: Libxfce4util: symbol='gettext': Unknown namespace for symbol 'gettext'
xfce-i18n.h:62: Warning: Libxfce4util: symbol='dgettext': Unknown namespace for symbol 'dgettext'
xfce-i18n.h:63: Warning: Libxfce4util: symbol='dcgettext': Unknown namespace for symbol 'dcgettext'
xfce-i18n.h:64: Warning: Libxfce4util: symbol='ngettext': Unknown namespace for symbol 'ngettext'
xfce-i18n.h:65: Warning: Libxfce4util: symbol='dngettext': Unknown namespace for symbol 'dngettext'
xfce-i18n.h:66: Warning: Libxfce4util: symbol='dcngettext': Unknown namespace for symbol 'dcngettext'

Closes: https://gitlab.xfce.org/xfce/libxfce4util/-/issues/7

1 files changed, 2 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index cf9e810..a501f69 100644
--- a/.gitignore
+++ b/.gitignore
@@ -50,4 +50,5 @@ libxfce4util/test-suite.log
 xfce4-kiosk-query/xfce4-kiosk-query
 xfce4-kiosk-query/xfce4_kiosk_query-main.o
 
-python-example/html/
+/nbproject
+/python-example/html/