N°2847 - Rework of MultiColumn / Column

- Remove unused HTML template
- Move SCSS files to match convention
- Move Column under MultiColumn to match convention (eg. ActivityPanel, PopoverMenu)
- Update PHPDoc

sources/application/UI/Layout/MultiColumn/Column/Column.php

@@ -0,0 +1,22 @@
+<?php
+/**
+ * @copyright   Copyright (C) 2010-2020 Combodo SARL
+ * @license     http://opensource.org/licenses/AGPL-3.0
+ */
+
+namespace Combodo\iTop\Application\UI\Layout\MultiColumn\Column;
+
+
+use Combodo\iTop\Application\UI\Layout\UIContentBlock;
+
+/**
+ * Class Column
+ *
+ * @package Combodo\iTop\Application\UI\Layout\MultiColumn\Column
+ * @internal
+ * @since 2.8.0
+ */
+class Column extends UIContentBlock {
+	// Overloaded constants
+	public const BLOCK_CODE = 'ibo-column';
+}