doxygen: add test

Closes #35351.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
libpng: add test

Closes #35352.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
fig, tutum: add conflicts_with.
libyaml: add test
libyaml: update 0.1.6 bottle.