Minimap as HUD element with API control

Features:
 * Define Minimap available modes (surface/radar, scale) from Lua, using player:set_minimap_modes()
 * New HUD elements for displaying minimap with custom size and placing
 * New minimap mode for displaying a texture instead of the map

src/network/networkprotocol.h

@@ -204,6 +204,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
 	PROTOCOL VERSION 39:
 		Updated set_sky packet
 		Adds new sun, moon and stars packets
+		Minimap modes
 */
 
 #define LATEST_PROTOCOL_VERSION 39
@@ -764,7 +765,18 @@ enum ToClientCommand
 		u8[len] formspec
 	*/
 
-	TOCLIENT_NUM_MSG_TYPES = 0x62,
+	TOCLIENT_MINIMAP_MODES = 0x62,
+	/*
+		u16 count // modes
+		u16 mode  // wanted current mode index after change
+		for each mode
+			u16 type
+			std::string label
+			u16 size
+			std::string extra
+	*/
+
+	TOCLIENT_NUM_MSG_TYPES = 0x63,
 };
 
 enum ToServerCommand