Display Unicode character for keys in HotkeySettingsControl (#2249)

* Fix HotkeyControl virtual key display

* A new interop project was setup to provide wrappers for C# projects
  that want to access functionality in the common project.

* Add assembly info

* Remove WIN32 configurations

src/common/interop/interop.h

@@ -0,0 +1,40 @@
+#pragma once
+
+#include <common\keyboard_layout.h>
+using namespace System;
+
+//https://docs.microsoft.com/en-us/cpp/dotnet/how-to-wrap-native-class-for-use-by-csharp?view=vs-2019
+namespace interop
+{
+public ref class LayoutMapManaged
+    {
+    public:
+        LayoutMapManaged() :
+            _map(new LayoutMap) {}
+
+        ~LayoutMapManaged()
+        {
+            delete _map;
+        }
+
+        String ^ GetKeyName(DWORD key) 
+        {
+            return gcnew String(_map->GetKeyName(key).c_str());
+        }
+
+        void Updatelayout()
+        {
+            _map->UpdateLayout();
+        }
+
+    protected:
+        !LayoutMapManaged()
+        {
+            delete _map;
+        }
+
+    private:
+        LayoutMap* _map;
+    };
+}
+