[Selectable] Number of bindings grow over time when programatically adding / removing selectable elements.

[Thomas Romera]

There is a performance issue on selectable.js when programmatically adding/removing elements that can be selected. The number of bindings selectable is working on is growing over time.

Example: ​https://jsfiddle.net/hzygug67/5/

Obviously with that small number of elements, it does not cause any issues, but when working with 300+ elements, it starts to be a problem when selecting / unselecting elements.

Only workaround I've found for now is to destroy and re-create the selectable widget.