plugins: Add Markdown preview

- https://github.com/iamcco/markdown-preview.nvim
- + `:format` in the lazy file

lua/lazy-configure.lua

@@ -226,4 +226,12 @@ require('lazy').setup({
   'tpope/vim-speeddating',
   -- vim-tabular
   'godlygeek/tabular',
+  -- MarkdownPreview without yarn or npm
+  {
+    "iamcco/markdown-preview.nvim",
+    cmd = { "MarkdownPreviewToggle", "MarkdownPreview", "MarkdownPreviewStop" },
+    ft = { "markdown", "pandoc" },
+    build = function() vim.fn["mkdp#util#install"]() end,
+  }
+
 }, {})