Open requested to merge work/zamundaaa/wayland-ownership into master
In a few places it was not obvious who is supposed to own the created objects or in which order they need to be destroyed. That's not completely fixed yet, but
Display is now at least more explicitly destroyed before interface extensions.
There also were some places where manual management could be very easily replaced 1:1 with
std::unique_ptr, and there were a lot of
CLEANUP macros in the autotests that did what
std::unique_ptr is for.