feat: add submenu control and brick

Related: #36 (closed)

Closes #36 (closed)

src/QUI/Menu/Bricks/Submenu.html

+{if $this->getAttribute('showTitle') && $this->getAttribute('frontendTitle')}
+<header class="control-header">
+    <h1>{$this->getAttribute('frontendTitle')}</h1>
+</header>
+{/if}
+
+{if $this->getAttribute('content') != ""}
+<div class="control-content">
+    {$this->getAttribute('content')}
+</div>
+{/if}
+
+{$Submenu->create()}
\ No newline at end of file