Refactor into standalone plugin

[clason]

Nvim-treesitter 1.0 (expected later this year) will completely remove the module system in order to significantly reduce complexity.

This means that nvim-treesitter-textobjects needs to be refactored into a standalone plugin, similarly to https://github.com/nvim-treesitter/nvim-treesitter-context or the indent.lua module in 1.0. (There's no need to hook into nvim-treesitter; textobjects should simply work if a suitable parser and queries are in runtimepath. This should also allow simplifying the setup as it no longer needs to be shoehorned into the nvim-treesitter setup structure.)

As a bonus, the incremental-selection (also removed in 1.0) feature could be integrated here as a in/an node object.

[TheLeoP]

Would a PR be welcome?

[clason]

Of course!

[TheLeoP]

Would the PR also have to remove the dependency on nvim-treesitter?

[clason]

Yes, that is the whole point!

[clason]

I consider this as completed by #523 and the follow-up fixes (thanks all!). Feel free to test it (if and only if you are testing nvim-treesitter main!) and report (or, better yet, fix) any regressions you find.