SCUMM/FM-TOWNS: start rewriting audio code

- Start rewriting audio code for FM-TOWNS versions of Loom, Indy3 and Monkey Island 1 using the recently added code in towns_audio.cpp (Zak should work the same way, but I can't test, since I don't own that one).
- All sound types (pcm, euphony and cd audio) now support volume and balance control (e.g. try walking into/out of the kitchen and opening/closing the door in the Scumm Bar in Monkey Island 1 or walking into/out of the circus tent).
- Pcm sounds now support proper loop start/end and note offsets (e.g. try out the hammer sound in the forge in LOOM for example).
- some other minor improvements
- The FM-Towns versions of Indy 4 and Monkey Island 2 are not affected. I don't have Monkey Island 2, but I presume that it will work like Indy 4. Adding support for these will be a separate task, since they work quite differently.

svn-id: r52198

engines/scumm/saveload.cpp

@@ -32,6 +32,7 @@
 #include "scumm/charset.h"
 #include "scumm/imuse_digi/dimuse.h"
 #include "scumm/imuse/imuse.h"
+#include "player_towns.h"
 #include "scumm/he/intern_he.h"
 #include "scumm/object.h"
 #include "scumm/resource.h"
@@ -447,6 +448,9 @@ bool ScummEngine::loadState(int slot, bool compat) {
 	// Update volume settings
 	syncSoundSettings();
 
+	if (_townsPlayer && (hdr.ver >= VER(81)))
+		_townsPlayer->restoreAfterLoad();
+
 	// Init NES costume data
 	if (_game.platform == Common::kPlatformNES) {
 		if (hdr.ver < VER(47))
@@ -1394,6 +1398,11 @@ void ScummEngine::saveOrLoad(Serializer *s) {
 		_imuse->save_or_load(s, this);
 	}
 
+
+	// Save/load FM-Towns audio status
+	if (_townsPlayer)
+		_townsPlayer->saveLoadWithSerializer(s);
+
 	//
 	// Save/load the charset renderer state
 	//