Fixes a bug where Dragula does not clean up after itself if containers are added or removed.
Fixes a bug where Dragula does not clean up after itself if containers are added or removed.

For example via ng-if and ng-repeat may produce or destroy containers.

Resolves https://github.com/looker/helltool/issues/26930

Derived from https://github.com/bevacqua/angularjs-dragula/pull/71/files

looker/angularjs-dragula,looker/angularjs-dragula