staging/content-type: Content type hint support
Some monitors expose a selector for the kind of content that will get displayed, allowing them to optimise their settings for this particular content type.
This protocol lets clients advertise which kind of content they expect to be displayed, per surface, so that the compositor can make more informed decisions about the content type to set a given output in.
See weston!698
Fixes #15.
Signed-off-by: Emmanuel Gil Peyrot linkmauve@linkmauve.fr