Docs: provide lua examples for heretics like myself.

Hey there fellow mouse user, glad to know I'm not the only heretic.

Since you mention this should work with Neovim 0.4+, how would we configure this in the context of using the `lazy.nvim` plugin manager? 

```lua
{
  'skywind3000/vim-quickui',
  config = function ()
     require('quickui').setup({}) -- ????? 
  end
}
```