Compilation speed comparison test

DO NOT USE THIS FOR ANY SORT OF PRODUCTION

This is a (historyless) fork of the Mediascanner project. It is only used for the purposes of comparing build speed between CMake and Meson. It is broken and handicapped in many ways:

• disable all things using dbus-cpp because it is not generally available
• disable Qml stuff
• tests will not run successfully (in fact don't run them at all)
• functionality is probably broken

If you wish to use Mediascanner, get it from its original web site. This repo should not be used for anything else except build speed comparison tests.