UI: Add text autoselect for source rename

UI/source-tree.cpp

@@ -259,6 +259,7 @@ void SourceTreeItem::EnterEditMode()
 	setFocusPolicy(Qt::StrongFocus);
 	boxLayout->removeWidget(label);
 	editor = new QLineEdit(label->text());
+	editor->selectAll();
 	editor->installEventFilter(this);
 	boxLayout->insertWidget(1, editor);
 	setFocusProxy(editor);