Merge branch 'api-bufferView-image-layout' into 'master'

vktApiBufferViewAccessTests: image cannot be created with COLOR_ATTACHMENT_OPTIMAL layout.

- According to spec, the only valid layouts in vkCreateImage are UNDEFINED and PREINITIALIZED
- This changes the test so image is cratead with valid layout, than transitioned to COLOR_ATTACHMENT_OPTIMAL using additional barrier

See merge request !207