Tooltips should be hidden first, then destroyed
Tooltips should be hidden first, then destroyed

We were simply destroying the tooltips instead of hiding them first, and that
was causing a flicker instead of the fadeout animation.

Also, we were needlessly connecting to the "leave-notify-event" signal.

[endlessm/eos-sdk#3946]

endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib,endlessm/eos-knowledge-lib