Add gamma support to ply-image.

src/ply-gamma.h

+/* ply-gamma.c - plymouth gamma setup via KMS
+ *
+ * Copyright (C) 2011, The Chromium OS Authors.
+ *
+ * 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 2, 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., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ *
+ */
+
+#ifndef PLY_GAMMA_H
+#define PLY_GAMMA_H
+
+#include <stdbool.h>
+
+#include "ply-utils.h"
+
+/* Set the gamma of the screen. */
+bool ply_gamma_set(const char* file);
+
+#endif /* PLY_GAMMA_H */