Partition: new class, container for Playlist and PlayerControl

This is the beginning of multi-player support.  There will be support
for multiple Partition objects in one MPD process.

src/Partition.hxx

@@ -0,0 +1,47 @@
+/*
+ * Copyright (C) 2003-2013 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * 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 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.
+ */
+
+#ifndef MPD_PARTITION_HXX
+#define MPD_PARTITION_HXX
+
+#include "Playlist.hxx"
+#include "PlayerControl.hxx"
+
+/**
+ * A partition of the Music Player Daemon.  It is a separate unit with
+ * a playlist, a player, outputs etc.
+ */
+struct Partition {
+	struct playlist playlist;
+
+	player_control pc;
+
+	Partition(unsigned max_length,
+		  unsigned buffer_chunks,
+		  unsigned buffered_before_play)
+		:pc(buffer_chunks, buffered_before_play) {
+		playlist_init(&playlist, max_length);
+	}
+
+	~Partition() {
+		playlist_finish(&playlist);
+	}
+};
+
+#endif