dbus_annotation: new protocol

The protocol allows clients or surfaces to be associated with DBus objects and interfaces.

This formalizes the ad-hoc extensions made to X and similar compositor-specific Wayland protocols for assorted tasks that boil down to associating DBus objects with windows/surfaces.

In user-facing terms, this would allow Unity-style application menus to be implemented in a cross-compositor manner on Wayland and provides a standard mechanism for applications such as Firefox and Google Chrome to program against.

Signed-off-by: Janet Blackquill uhhadd@gmail.com