cookbook: Clarify how signals are emitted during looped animation
cookbook: Clarify how signals are emitted during looped animation

Added a comment to the example code about how timeline
emits "completed" during looped animation, while the
animation itself doesn't.

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