Code review comment for lp:~canonical-dx-team/unity/unity.startup-notification

Looks good, some notes + questions:

- You need to add a dep for libstartup-notification-1.0 to CMakeLists.txt::UNITY_PLUGIN_DEPS

- The quirks, they seem to be all booleans, should they just be bit flags? I'm not sure how it'll impact API, though...