Edit any files in user dir

templates/edit.html

@@ -1,8 +1,18 @@
 {{ define "title" }}編輯{{ end }}
 {{ define "main" }}
 <h1>編輯帳本</h1>
-<form action="/edit" method="POST">
-    <textarea name="data" rows="15" cols="40">{{ . }}</textarea><br>
+<aside>
+    <ul>
+        {{ range .FileList }}
+        <li><a href="/edit/{{ . }}">{{ . }}</a></li>
+        {{ end }}
+    </ul>
+</aside>
+
+<p>{{ .FileName }}{{ if not .Exists }} - New file{{ end }}</p>
+
+<form action="/edit/{{ .FileName }}" method="POST">
+    <textarea name="data" rows="15" cols="40">{{ .Data }}</textarea><br>
     <input type="submit" value="儲存">
 </form>
 {{ end }}