Having to maintain and sync the module identifier in multiple places and
variants runs the chance of missing one place when changing it.
Also is having to explicitly writing the qmldir file cumbersome when the
buildsystem already has all needed information.
For now there is just one macro, for the installation of C++ plugins. Future
extension might be macros for the installation of QML files modules.
Further extension could also allow to specifiy additional content of theThe built-in support for generating/updating a qmltypes file in the sources
qmldir.merges the main functionality of ECMGenerateQmlTypes,