Add ID's to buttons in configure-feed

Add ID's to be able to individually target buttons inside the configure feeds (Subscriptions Management & Import/Export) buttons.

app/layout/aside_feed.phtml

@@ -12,8 +12,8 @@
 
 	<?php if (FreshRSS_Auth::hasAccess()) { ?>
 	<div class="stick configure-feeds no-mobile">
-		<a class="btn btn-important" href="<?php echo _url('subscription', 'index'); ?>"><?php echo _t('index.menu.subscription'); ?></a>
-		<a class="btn btn-important" href="<?php echo _url('importExport', 'index'); ?>"><?php echo _i('import'); ?></a>
+		<a id="btn-subscription" class="btn btn-important" href="<?php echo _url('subscription', 'index'); ?>"><?php echo _t('index.menu.subscription'); ?></a>
+		<a id="btn-importExport" class="btn btn-important" href="<?php echo _url('importExport', 'index'); ?>"><?php echo _i('import'); ?></a>
 	</div>
 	<?php } elseif (FreshRSS_Auth::accessNeedsLogin()) { ?>
 	<a href="<?php echo _url('index', 'about'); ?>"><?php echo _t('index.menu.about'); ?></a>