Describe the new feature

I recently made a change to user can use a user configuration file with code I committed. 0644bc0

However, it still only works on the command line. Working from the command line would be inconvenient for most users compared to GUI environments. In fact, there were some people who used this program for education in related issues.

So I propose to provide two menus as follows in GUI environment.

• Import Configuration
• Export Configuration
  
  and I will also provide the option to permanently save the configuration(Windows registry or specified path by QSettings class) so that the user doesn't load the configuration file every time they run the DB4S. What do you think? 😄
  
  *It's not included in the screenshot, but it would be nice to warn that if click 'Yes', existing settings may be deleted.

Additional info

Please answer these questions before submitting your feature request.

Is your feature request related to an issue? Please include the issue number.

#2317

Does this feature exist in another product or project? Please provide a link.

Many

Do you have a screenshot? Please add screenshots to help explain your idea.

Already attached above.