actor: Add ::transitions-completed signal
actor: Add ::transitions-completed signal

While you can get a per-transition notification of completion, it can be
convenient to also have a way to notify that all the transitions
involving an actor are complete. A simple signal triggered by the
removal of the last transition fits the bill pretty neatly.

djdeath/clutter,GNOME/clutter,ebassi/clutter,djdeath/clutter,djdeath/clutter-android,djdeath/clutter-multithreaded,collects/clutter,heysion/clutter-clone,Distrotech/clutter,djdeath/clutter,collects/clutter,djdeath/clutter,collects/clutter,djdeath/clutter-multithreaded,jigpu/clutter,jigpu/clutter,kerrickstaley/clutter-vala,jigpu/clutter,GNOME/clutter,heysion/clutter-clone,GNOME/clutter,ebassi/clutter,djdeath/clutter-android,ebassi/clutter,djdeath/clutter,heysion/clutter-clone,ebassi/clutter,djdeath/clutter-multithreaded,heysion/clutter-clone,Distrotech/clutter,kerrickstaley/clutter-vala,Distrotech/clutter,Distrotech/clutter,djdeath/clutter-android,jigpu/clutter,djdeath/clutter-multithreaded,Distrotech/clutter,GNOME/clutter,GNOME/clutter,kerrickstaley/clutter-vala,djdeath/clutter-android,kerrickstaley/clutter-vala,Distrotech/clutter,djdeath/clutter,ebassi/clutter,djdeath/clutter-android,heysion/clutter-clone,jigpu/clutter,collects/clutter,jigpu/clutter,collects/clutter