add logout link to account page

templates/account.html.ep

 <h1>Account</h1>
 % my $acc = get_user_data();
 <div class="row">
-	<table class="striped">
-		<tr>
-			<th scope="row">Name</th>
-			<td><%= $acc->{name} %></td>
-		</tr>
-		<tr>
-			<th scope="row">Mail</th>
-			<td><%= $acc->{email} %></td>
-		</tr>
-		<tr>
-			<th scope="row">Registriert am</th>
-			<td><%= $acc->{registered_at}->strftime('%d.%m.%Y %H:%M') %></td>
-		</tr>
-	</table>
+	<div class="col s12">
+		<table class="striped">
+			<tr>
+				<th scope="row">Name</th>
+				<td><%= $acc->{name} %></td>
+			</tr>
+			<tr>
+				<th scope="row">Mail</th>
+				<td><%= $acc->{email} %></td>
+			</tr>
+			<tr>
+				<th scope="row">Registriert am</th>
+				<td><%= $acc->{registered_at}->strftime('%d.%m.%Y %H:%M') %></td>
+			</tr>
+		</table>
+	</div>
+</div>
+<div class="row">
+	<div class="col s1 m1 l3">
+	</div>
+	<div class="col s10 m10 l6 center-align">
+		%= form_for 'logout' => begin
+			%= csrf_field
+			<button class="btn waves-effect waves-light" type="submit" name="action" value="logout">
+				Abmelden
+			</button>
+		%= end
+	</div>
+	<div class="col s1 m1 l3">
+	</div>
 </div>
 
 <h1>Export</h1>