Update example: youcompleteme#Enable is no longer needed

Close #501

README.md

@@ -182,9 +182,9 @@ Plug 'kovisoft/paredit', { 'for': ['clojure', 'scheme'] }
 " On-demand loading on both conditions
 Plug 'junegunn/vader.vim',  { 'on': 'Vader', 'for': 'vader' }
 
-" Code to execute when the plugin is loaded on demand
-Plug 'Valloric/YouCompleteMe', { 'for': 'cpp' }
-autocmd! User YouCompleteMe if !has('vim_starting') | call youcompleteme#Enable() | endif
+" Code to execute when the plugin is lazily loaded on demand
+Plug 'junegunn/goyo.vim', { 'for': 'markdown' }
+autocmd! User goyo.vim echom 'Goyo is now loaded!'
 ```
 
 `for` option is generally not needed as most plugins for specific file types