Please add Wayflan

[samuel-hunter]

https://git.sr.ht/~shunter/wayflan/

Notes for building, changes have been made upstream to systems cl-xdg and posix-shm, and the system input-event-codes was created to make wayflan/examples possible. However the unit tests do not depend on wayflan/examples, and so does not need these dependencies to load.

Thanks!