Keep a map of import aliases and use this when generating basename

currently using
import QtQuick.Controls as QtControls would create

using namespace QtControls, which isn't easily mappable. By storing a
map we can use QtQuick::Controls:: as our base name classname

--
Combined with some patches in qtdoc (https://codereview.qt-project.org/#/c/92014/)
we can now link against their .tags file and show full inheritance