GUI: wire up the code for custom keybinds

still no way to set them up, and four are missing
please be patient

src/engine/engine.cpp

@@ -5256,6 +5256,17 @@ void DivEngine::muteChannel(int chan, bool mute) {
   isBusy.unlock();
 }
 
+void DivEngine::unmuteAll() {
+  isBusy.lock();
+  for (int i=0; i<chans; i++) {
+    isMuted[i]=false;
+    if (disCont[dispatchOfChan[i]].dispatch!=NULL) {
+      disCont[dispatchOfChan[i]].dispatch->muteChannel(dispatchChanOfChan[i],isMuted[i]);
+    }
+  }
+  isBusy.unlock();
+}
+
 int DivEngine::addInstrument(int refChan) {
   isBusy.lock();
   DivInstrument* ins=new DivInstrument;

src/engine/engine.h

@@ -368,6 +368,9 @@ class DivEngine {
     // set mute status
     void muteChannel(int chan, bool mute);
 
+    // unmute all
+    void unmuteAll();
+
     // get channel name
     const char* getChannelName(int chan);
 

src/gui/gui.h

@@ -84,7 +84,16 @@ enum FurnaceGUIWindows {
   GUI_WINDOW_WAVE_EDIT,
   GUI_WINDOW_SAMPLE_LIST,
   GUI_WINDOW_SAMPLE_EDIT,
-  GUI_WINDOW_MIXER
+  GUI_WINDOW_MIXER,
+  GUI_WINDOW_ABOUT,
+  GUI_WINDOW_SETTINGS,
+  GUI_WINDOW_DEBUG,
+  GUI_WINDOW_VOL_METER,
+  GUI_WINDOW_STATS,
+  GUI_WINDOW_COMPAT_FLAGS,
+  GUI_WINDOW_PIANO,
+  GUI_WINDOW_NOTES,
+  GUI_WINDOW_CHANNELS,
 };
 
 enum FurnaceGUIFileDialogs {
@@ -443,7 +452,8 @@ class FurnaceGUI {
   bool pianoOpen, notesOpen, channelsOpen;
   SelectionPoint selStart, selEnd, cursor;
   bool selecting, curNibble, orderNibble, extraChannelButtons, followOrders, followPattern, changeAllOrders;
-  FurnaceGUIWindows curWindow;
+  bool collapseWindow, closeWindow;
+  FurnaceGUIWindows curWindow, nextWindow;
   float peak[2];
 
   // bit 31: ctrl
@@ -566,6 +576,8 @@ class FurnaceGUI {
   void finishSelection();
 
   void moveCursor(int x, int y, bool select);
+  void moveCursorPrevChannel(bool overflow);
+  void moveCursorNextChannel(bool overflow);
   void moveCursorTop();
   void moveCursorBottom();
   void editAdvance();