Challenges in adapting glmark2 to Wayland

glmark2 has come a long way since it began life as glmark. We have seen the addtition of new window system interfaces (via the Canvas object) both from within the project (Android) as well as from community contributions (offscreen rendering support). Based upon the infrastructure required to support all of this, it should be reasonable to add Wayland support to the glmark2 Canvas. There will still be some challenges, and we will explore those here.