gnome: add autostart functionality

Autostart is enabled by creating a symlink to gnome-ring.desktop
in $XDG_CONFIG_HOME/autostart (this is supported by all XDG
compliant desktop environments.
This is enabled by default and will be done the first time the
client is launched and the setting is checked on every launch.
This patch also adds a GSettings schema for the client to keep
track of the client settings (for now just the autostart enabled).

To support non-installed builds, the gschema is compiled to the
directory of the binary by default. The client first checks for
the .desktop and the compiled gschema in the local directory of
the binary.

A patch is required in the packaging branch to support the new
functionality.

Refs #74056

Change-Id: Ife9c8149e3225ab765dc1d2472ca0fd44ad35691
diff --git a/src/utils/files.h b/src/utils/files.h
new file mode 100644
index 0000000..b912790
--- /dev/null
+++ b/src/utils/files.h
@@ -0,0 +1,44 @@
+/*
+ *  Copyright (C) 2015 Savoir-Faire Linux Inc.
+ *  Author: Stepan Salenikovich <stepan.salenikovich@savoirfairelinux.com>
+ *
+ *  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, write to the Free Software
+ *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301 USA.
+ *
+ *  Additional permission under GNU GPL version 3 section 7:
+ *
+ *  If you modify this program, or any covered work, by linking or
+ *  combining it with the OpenSSL project's OpenSSL library (or a
+ *  modified version of that library), containing parts covered by the
+ *  terms of the OpenSSL or SSLeay licenses, Savoir-Faire Linux Inc.
+ *  grants you additional permission to convey the resulting work.
+ *  Corresponding Source for a non-source form of such a combination
+ *  shall include the source code for the parts of OpenSSL used as well
+ *  as that of the covered work.
+ */
+
+#ifndef _FILES_H
+#define _FILES_H
+
+#include <gio/gio.h>
+
+G_BEGIN_DECLS
+
+void autostart_symlink(gboolean autostart);
+
+GSettingsSchema *get_ring_schema();
+
+G_END_DECLS
+
+#endif /* _FILES_H */