simplify linear_set

alib2std/src/extensions/linear_set.hpp

@@ -544,8 +544,7 @@ public:
 	 * \param il the source of values represented by initializer list
 	 */
 	void insert (std::initializer_list<T> il) {
-		m_data.insert ( m_data.end ( ), std::move ( il ) );
-		sort_unique ( );
+		insert ( il.begin ( ), il.end ( ) );
 	}
 	/**