Add http caching draft

Author: RoyalIcing

apps/components_guide_web/lib/components_guide_web/controllers/web_controller.ex

@@ -6,7 +6,7 @@ defmodule ComponentsGuideWeb.WebController do
     render(conn, "index.html", article: "intro")
   end
 
-  @articles ["url", "promise"]
+  @articles ["url", "promise", "http-caching"]
 
   def show(conn, %{"id" => article}) when article in @articles do
     render(conn, "index.html", article: article)

apps/components_guide_web/lib/components_guide_web/templates/web/_nav.html.eex

@@ -3,5 +3,6 @@
     <li><%= link("Why?", to: '/web') %>
     <li><%= link("URL", to: '/web/url') %>
     <li><%= link("Promise", to: '/web/promise') %>
+    <li><%= link("HTTP Caching", to: '/web/http-caching') %>
   </ul>
 </nav>

apps/components_guide_web/lib/components_guide_web/templates/web/http-caching.html.md

@@ -0,0 +1,11 @@
+# HTTP Caching
+
+## Initial response
+
+## When server has same etag
+
+## When server has not been modified since
+
+## When server has different etag
+
+## When server has been modified since