* drop split devices, rebase
* add fallback to opengl if vulkan is not available
* addressed review
* ensure present image references are incremented and decremented when necessary
* allow changing vsync for vulkan
* fix screenshot on avalonia vulkan
* save favorite when toggled
* improve sync between popups
* use separate devices for each new window
* fix crash when closing window
* addressed review
* don't create the main window with immediate mode
* change skia vk delegate to method
* update vulkan throwonerror
* addressed review
