Move plugin examples from README to optional plugin files (#831)

* Move autopairs example from README to an optional plugin

* Move neo-tree example from README to an optional plugin

init.lua

@@ -854,6 +854,8 @@ require('lazy').setup({
   -- require 'kickstart.plugins.debug',
   -- require 'kickstart.plugins.indent_line',
   -- require 'kickstart.plugins.lint',
+  -- require 'kickstart.plugins.autopairs',
+  -- require 'kickstart.plugins.neo-tree',
 
   -- NOTE: The import below can automatically add your own plugins, configuration, etc from `lua/custom/plugins/*.lua`
   --    This is the easiest way to modularize your config.