timeline: No autotrans between elements in same toplevel container
timeline: No autotrans between elements in same toplevel container

This makes no sense, we ended up creating/removing tons of transition
while moving groups

cfoch/gst-editing-services,cfoch/ges,pitivi/gst-editing-services,pitivi/gst-editing-services,cfoch/ges,cfoch/ges,cfoch/gst-editing-services,cfoch/ges,pitivi/gst-editing-services,cfoch/gst-editing-services,cfoch/gst-editing-services,pitivi/gst-editing-services