Enable using Prism for syntax highlighting (#735)

* Enable user to use prism.js as syntax highlighter

* add package-lock

* if 'usePrism' is true, use prismjs on all languages

* don't get lang by hljs if use prism

* Update api-site-config.md

* Update api-doc-markdown.md

* only load prism css when usePrism is true

lib/static/css/main.css

@@ -1870,4 +1870,4 @@ footer .social {
   footer.nav-footer {
     flex-shrink: 0;
   }
-}
+}