Update all deprecated Material Design icons

All Material Design icons should now use their new code points.
This unbreaks gBar with Nerd Fonts v3.0.0

src/AudioFlyin.cpp

@@ -47,11 +47,11 @@ namespace AudioFlyin
                     muted = info.sinkMuted;
                     if (info.sinkMuted)
                     {
-                        icon->SetText("ﱝ");
+                        icon->SetText("󰝟");
                     }
                     else
                     {
-                        icon->SetText("墳");
+                        icon->SetText("󰕾 ");
                     }
                 }
             }

src/Bar.cpp

@@ -103,13 +103,13 @@ namespace Bar
             else if (info.devices.empty())
             {
                 btIconText->SetClass("bt-label-on");
-                btIconText->SetText("");
+                btIconText->SetText("󰂯");
                 btDevText->SetText("");
             }
             else
             {
                 btIconText->SetClass("bt-label-connected");
-                btIconText->SetText("");
+                btIconText->SetText("󰂱");
                 std::string btDev;
                 std::string tooltip;
                 for (auto& dev : info.devices)

src/BluetoothDevices.cpp

@@ -256,7 +256,7 @@ namespace BluetoothDevices
         headerBox->SetClass("bt-header-box");
         {
             auto headerText = Widget::Create<Text>();
-            headerText->SetText(" Bluetooth");
+            headerText->SetText("󰂯 Bluetooth");
             headerBox->AddChild(std::move(headerText));
 
             auto headerRefresh = Widget::Create<Button>();

src/System.cpp

@@ -416,19 +416,19 @@ namespace System
     {
         if (dev.type == "input-keyboard")
         {
-            return " ";
+            return "󰌌 ";
         }
         else if (dev.type == "input-mouse")
         {
-            return " ";
+            return "󰍽 ";
         }
         else if (dev.type == "audio-headset")
         {
-            return " ";
+            return "󰋋 ";
         }
         else if (dev.type == "input-gaming")
         {
-            return "調 ";
+            return "󰖺 ";
         }
         return " ";
     }