Add .gitignore for Haxe

[sech1p]

Reasons for making this change

TODO

I decided to contribute here with .gitignore for Haxe toolkit, because I felt lack of it during developing Haxe project in Visual Studio Code with gitignore extension which is based on this repository.

Links to documentation supporting these rule changes

https://github.com/therecipe/haxe

If this is a new template

Link to application or project’s homepage: haxe.org

Merge and Approval Steps

• Confirm that you've read the contribution guidelines and ensured your PR aligns
• Ensure CI is passing
• Get a review and Approval from one of the maintainers

[wirecat]

@sech1p could you provide more documentation on why each line in the .gitignore is relevant?
I can't find official recommendations on the haxe repo.

Also, we don't accept gitignore templates with the DS_Store entry in it. The template should only target contents relevant to the haxe language.

Very happy to accept a haxe template once we address these concerns. :)

[wirecat]

Duplicate of #3455

[kLabz]

This proposed template doesn't make much sense for Haxe

[wirecat]

Closing as a duplicate of #3455 which we just merged.

Please feel free to open changes to the template, but with additional documentation to justify new rules.