protocol: introduce wl_surface.get_release
This new request allows clients to get per-surface-commit buffer release events. It supersedes wl_buffer.release.
This functionality is also available via the linux-explicit-synchronization protocol, but requires the compositor to also support Linux synchronization fences. Adding this new request to the core protocol allows any compositor to implement the functionality.
Signed-off-by: Simon Ser contact@emersion.fr Closes: #203