Change wording in template.

templates/index.html

@@ -1,7 +1,7 @@
 {{ template "header" }}
 <form method="post" action="feeds">
 	<fieldset>
-		<legend>Send tweet</legend>
+		<legend>Send twtxt</legend>
 
 		<div>
 			<label for="twt">Message</label>