Release 1.6.0

- added Jsb::BEHAVIOURS_APPLIED-Event which is fired as soon as all
  behaviours have been applied. May be called multiple times (on
  ajax and stuff)
- added `.dontLeak()`-Method on off-Handler to remove the instance
  as soon as an instance got removed by triggering: Jsb::REMOVE_INSTANCE
  with `this` of the instance