Major OpenDatabaseUserControl refactor, now has proper ViewModel

Status text and password box border colors are updated according to database status
Update composite key in Settings work
Some code cleanup

ModernKeePass/Common/NotifyPropertyChangedBase.cs

@@ -8,7 +8,7 @@ namespace ModernKeePass.Common
     {
         public event PropertyChangedEventHandler PropertyChanged;
 
-        protected void OnPropertyChanged([CallerMemberName] string propertyName = "")
+        protected void OnPropertyChanged(string propertyName = "")
         {
             PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
         }