Bug 759105 - Patch to add icon theme selection

Add support for custom icon themes much like custom theme
support. There is still work to be done but this is the
basic functionality.

app/gui/icon-themes.h

@@ -0,0 +1,34 @@
+/* GIMP - The GNU Image Manipulation Program
+ * Copyright (C) 1995 Spencer Kimball and Peter Mattis
+ *
+ * icon-themes.h
+ * Copyright (C) 2015 Benoit Touchette
+ *
+ * This program 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 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef __ICONS_THEMES_H__
+#define __ICONS_THEMES_H__
+
+
+void     icon_themes_init          (Gimp        *gimp);
+void     icon_themes_exit          (Gimp        *gimp);
+
+gchar ** icon_themes_list_themes   (Gimp        *gimp,
+                                    gint        *n_themes);
+GFile  * icon_themes_get_theme_dir (Gimp        *gimp,
+                                    const gchar *theme_name);
+
+
+#endif /* __ICONS_THEMES_H__ */