Add http2 server push links

categories/web.md

@@ -3,6 +3,8 @@
 - [HTML](#html)
 - [HTTP 2](#http-2)
     - [HTTP server push](#http-server-push)
+- [HTTP server-sent events](#http-server-sent-events)
+        - [Links](#links)
 - [CSS3](#css3)
 - [CORS](#cors)
 - [CDN](#cdn)
@@ -21,6 +23,20 @@
 
 Server push some related resource before the browser sends the request. .e.g. Browser request index.html, and then server response with index.html and also take the initiative to push style.css and index.js to frontend.
 
+Frames:
+
+* HEADERS
+* PUSH_PROMISE
+* DATA
+* RST_STREAM
+
+
+# HTTP server-sent events
+
+
+### Links
+* [A Comprehensive Guide To HTTP/2 Server Push](https://www.smashingmagazine.com/2017/04/guide-http2-server-push/)
+
 
 # CSS3