NUI talk screen

[BenjaminAmos]

Description

This pull request converts the Talk screen to NUI. It should functionally identically to before, although there may be some minor visual differences.

Before

After

Testing

• Start a new game (or continue an existing one)
• Fly towards the starting station until the Talk button is enabled
• Verify that the talk screen opens when you click on the Talk button
• Verify that each of the buttons on the talk screen behaves as before e.g.
  • Verify that the buy screen opens when you click on the Buy button (or press the B key)
  • Verify that the sell screen opens when you click on the Sell button (or press the S key)
  • Verify that the Change Ship screen opens when you click on the Change Ship button (or press the C key)
  • Verify that the Hire Ship screen opens when you click on the Hire button (or press the H key)
  • Verify that the talk screen closes when you click on its Close button (or press the Escape key)
• Test that this works for both the starting station and the stations found on planets

Notes

• This depends on #631, #636 and #638.
• Until #631, #636 and #638 are merged, it might be easier to view the changes made in this pull request by viewing the diff between this and #638 at https://github.com/BenjaminAmos/DestinationSol/compare/nui-game-menu...nui-talk-screen.

[Mystic-Slice]

Although, I stumbled upon a new bug. Two NUI menus can be opened at the same time. This should not be allowed. But seeing that it is not isolated to this particular PR, It would make sense to fix this after merging PRs #636 #638 and #639.

https://user-images.githubusercontent.com/73862377/154794401-7aeaf202-7e7c-47d6-a60b-d239e92e36dc.mp4

Another thing you can observe here is that when I open Inventory by clicking Items, the Mercs button just works like a close button for the Inventory. It does not make sense to me. I would want the Inventory to close and the Mercenary screen to open. This is not a bug caused by NUI. The menus work the same way in the develop branch also (the old UI).

[BenjaminAmos]

This was replaced by #667.