add cutoff and pulse width slides for C64, SID2 and SID3

Also add clipping for ADSR, duty and cutoff when in instrument types you go SID3 -> SID2 or SID2 -> C64 or SID3 -> C64

src/engine/playback.cpp

@@ -278,6 +278,9 @@ const char* cmdName[]={
   "SID3_FILTER_CONNECTION",
   "SID3_FILTER_MATRIX",
   "SID3_FILTER_ENABLE",
+
+  "DIV_CMD_C64_PW_SLIDE",
+  "DIV_CMD_C64_CUTOFF_SLIDE",
 };
 
 static_assert((sizeof(cmdName)/sizeof(void*))==DIV_CMD_MAX,"update cmdName!");