After https://github.com/nvim-treesitter/nvim-treesitter/issues/470,
we decided to use `@conditional` for ternary operator instead of
operator despite `@conditional` is documented for keywords only.
A sub-scoping can make it easier for people to highlight this operator
group differently.
Also unify the usage of `@conditional...` across languages.
* Add slint parser
* Mark slint as experimental
* Remove filetype and add slint to the lockfile
* Update queries
* Update varibable.builtin's and repeats
* Update slint true false
* Change export back to keyword
* Change export back to include :)