Adding createable prop to allow creating of options which were not found

[Gregoor]

I required this feature which is afaik also present in Selectize. Let me know if I missed anything or you want to merge it and also need documentatoin.

Also tried to stick to your coding style and lint went through fine.

[JedWatson]

Thanks @Gregoor. I'd like to have a think on the implementation of this, as it would be good to also allow a callback for creating a new option (e.g. if a tag is required in the database to accept an ID - useful for SPAs). Will get back to you soon.

[AlexMeah]

👍 Need this for group selection/creation

[guzart]

What are your thoughts so far @JedWatson ?

Am thinking probably a createOption property that takes a function which returns the option to be added. The function could have the following signature function(value:string, [callback:func]):object.

By default the added option would be { value: _optionsFilterString, label: _optionsFilterString}. If a createOption function is specified it could work synchronously by returning the option to be added, or asynchronously if a callback function is specified as the second parameter (arity of 2)

[barsukov]

+1

[dehbmarques]

+1

[dcousens]

Closing, this was added in #151