Add Vue3 support for vim and neovim

[wgxh]

Feature request

I use coc extension 'coc-vetur', But 'coc-vetur' does not seem to support Vue3.
I have posted a feature request on coc-vetur, but its author says, 'Send your feature request to https://www.npmjs.com/package/vls.', See this.
I think This language server should include these support for Vue3 feature:

1. Support <script setup>.
2. Auto completion CSS v-bind().
3. Auto completion variable names in html interpolation expression.(Variables is define in setup function)

I hope this language server can add vue3 support for vim/neovim, Thanks!

[yoyo930021]

Vetur and vls support vue3.
but they don't support <script setup>. Please follow #2296.

Auto completion CSS v-bind().

Please open a new issue about this.

[wgxh]

Vetur and vls support vue3.
but they don't support <script setup>. Please follow #2296.

Auto completion CSS v-bind().
Please open a new issue about this.

Oh, Thanks! I hope this language server support <script setup> feature very soon!