Added add function

[pjona]

No description provided.

[RamonSmit]

You're working quite hard on this one 👍

[pjona]

@RamonSmit can you make new release on GitHub?

[pjona]

@RamonSmit I also thinking about adding ESLint, and few events.

[RamonSmit]

New release to 1.2.5?

[pjona]

Yes, please.

[RamonSmit]

Done :-)

[RomanBurunkov]

Hi @pjona,

I've tested add method and found out one issue when adding item with parent_id.
When adding first child to parent with id parent_id, add method doesn't add expand/colapse buttons and further we have no chance to add then from user side. Looks like we should use setParent method which already exist. But I'm not quite sure where to add it.

[pjona]

@RomanBurunkov you are right, I will try to fix it. Can you create a issue with it?

[RomanBurunkov]

@pjona,

Issue 66 has been added ;)

Thanks, Roman.