Partial Conversion for Godot 4

[rngesus-wept]

• Naive conversion of project to Godot 4. This is done solely by attempting to Import the project in Godot 4.1.
  • Also includes a .gitignore entry for .godot/, which I guess wasn't a thing in Godot 3 but is now.
• Update GUT from 7.4.1 to 9.0.1.
  • This is the change that fixes a large number of errors, including the coroutine-related stuff mentioned in https://github.com/db0/godot-card-game-framework/issues/178#issuecomment-1523320966. It is done by deleting the entirety of addons/gut, disabling the plugin, then reinstalling a fresh copy from AssetLib and enabling the plugin.
  • There is probably a better approach somehow, in terms of project management, for making sure that version of GUT associated with this project stays in lockstep with the most recent developments in that project, rather than keeping a full copy checked out within this one.

49 errors remain (down from 8000+). I have made no effort within this pull request to check that any existing unit tests operate correctly with the new version of GUT.

[ski-freak]

When roughly could I expect godot 4 support from the card game framework? How far along is it? Will it be a few months? years?