Change HTML input tags to use HTML5 syntax. (#1617)

In XHTML, the <input> tag must be properly closed, like this `<input />`.  In HTML5 the `<input>` tag has no ending slash.  https://www.w3schools.com/tags/tag_input.asp

README.md

@@ -824,12 +824,12 @@ form.html
 <form action="/" method="POST">
     <p>Check some colors</p>
     <label for="red">Red</label>
-    <input type="checkbox" name="colors[]" value="red" id="red" />
+    <input type="checkbox" name="colors[]" value="red" id="red">
     <label for="green">Green</label>
-    <input type="checkbox" name="colors[]" value="green" id="green" />
+    <input type="checkbox" name="colors[]" value="green" id="green">
     <label for="blue">Blue</label>
-    <input type="checkbox" name="colors[]" value="blue" id="blue" />
-    <input type="submit" />
+    <input type="checkbox" name="colors[]" value="blue" id="blue">
+    <input type="submit">
 </form>
 ```
 

examples/realtime-advanced/resources/room_login.templ.html

@@ -79,19 +79,19 @@
                                 <label class="sr-only" for="chat-message">Message</label>
                                 <div class="input-group">
                                     <div class="input-group-addon">{{.nick}}</div>
-                                    <input type="text" name="message" id="chat-message" class="form-control" placeholder="a message" value="" />
+                                    <input type="text" name="message" id="chat-message" class="form-control" placeholder="a message" value="">
                                 </div>
                             </div>
-                            <input type="submit" class="btn btn-primary" value="Send" />
+                            <input type="submit" class="btn btn-primary" value="Send">
                         </form>
                         {{else}}
                         <form action="" method="get" class="form-inline">
                             <legend>Join the SSE real-time chat</legend>
                             <div class="form-group">
-                                <input value='' name="nick" id="nick" placeholder="Your Name" type="text" class="form-control" />
+                                <input value='' name="nick" id="nick" placeholder="Your Name" type="text" class="form-control">
                             </div>
                             <div class="form-group text-center">
-                                <input type="submit" class="btn btn-success btn-login-submit" value="Join" />
+                                <input type="submit" class="btn btn-success btn-login-submit" value="Join">
                             </div>
                         </form>
                         {{end}}

examples/realtime-chat/template.go

@@ -35,9 +35,9 @@ var html = template.Must(template.New("chat_room").Parse(`
     <h1>Welcome to {{.roomid}} room</h1>
     <div id="messages"></div>
     <form id="myForm" action="/room/{{.roomid}}" method="post"> 
-    User: <input id="user_form" name="user" value="{{.userid}}"></input> 
-    Message: <input id="message_form" name="message"></input> 
-    <input type="submit" value="Submit" /> 
+    User: <input id="user_form" name="user" value="{{.userid}}">
+    Message: <input id="message_form" name="message">
+    <input type="submit" value="Submit"> 
     </form>
 </body>
 </html>