v2.4.0

Bugfixes:

• Call setPresentationValue in onAttach method (#33)
• Track additional items that were not returned by findItemByLabel (#35)
• Support adding additional items through setValue (#36)
  • If additional items are allowed, non-existing items are always tracked as additional items.
  • If additional items are not allowed, then setPresentationValue sanitizes the input by ignoring such items.
• Restore presentation value on exception case (#45)
• Fire created/removed events when the value changes (#48, #49): fix that the events are not fired when the value is modified from server side, and the item is not available from the removed listener when the removal originates from the client.

Other changes:

• Deprecate duplicated methods