Add Haxe language support

[spindlebink]

There may be more roots indicators to add, but I'm a Haxe newbie so I only added the ones I know about for now.

[kirawi]

Can you run cargo xtask docgen and commit the changes?

@@ -49,6 +49,7 @@
 | graphql | ✓ |  |  |  |
 | hare | ✓ |  |  |  |
 | haskell | ✓ |  |  | `haskell-language-server-wrapper` |
+| haxe | ✓ |  |  |  |
 | hcl | ✓ |  | ✓ | `terraform-ls` |
 | heex | ✓ | ✓ |  |  |
 | html | ✓ |  |  | `vscode-html-language-server` |

Or manually add this to lang-support.md

[spindlebink]

Neither the parser nor queries are my work: I directly copied the queries from the repo into the queries folder, noticed the highlighting seemed to be working, and pushed without inspecting the parsing results. I'll address the review you've put here, but also I'm just beginning to learn Haxe, so for actual iteration on the parser we'd need somebody who knows the syntax better than I do.