shell: Make the application a GtkApplication subclass

This promotes better encapsulation and allows us to move
application logic out of main() and rename the confusingly
named control-center.c to main.c

https://bugzilla.gnome.org/show_bug.cgi?id=692174

shell/main.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2009, 2010 Intel, Inc.
+ * Copyright (c) 2010 Red Hat, Inc.
+ *
+ * The Control Center is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * The Control Center is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with the Control Center; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ *
+ * Author: Thomas Wood <thos@gnome.org>
+ */
+
+#include "config.h"
+
+#include <stdlib.h>
+#include <glib/gi18n.h>
+#include <gtk/gtk.h>
+#include <egg-list-box.h>
+
+#ifdef GDK_WINDOWING_X11
+#include <X11/Xlib.h>
+#endif
+
+#include "cc-application.h"
+
+int
+main (int argc, char **argv)
+{
+  GtkApplication *application;
+  int status;
+
+  bindtextdomain (GETTEXT_PACKAGE, GNOMELOCALEDIR);
+  bind_textdomain_codeset (GETTEXT_PACKAGE, "UTF-8");
+  textdomain (GETTEXT_PACKAGE);
+
+#ifdef GDK_WINDOWING_X11
+  XInitThreads ();
+#endif
+
+  g_type_ensure (egg_list_box_get_type ());
+
+  application = cc_application_new ();
+  status = g_application_run (G_APPLICATION (application), argc, argv);
+
+  g_object_unref (application);
+
+  return status;
+}