Forked as activeadmin-searchable_select

[tf]

Hi Mark,

just wanted to let you know that I have created an Active Admin plugin called activeadmin-searchable_select which is based on the code of this repository. I mainly needed a way to fetch options via ajax and define JSON endpoints to provide these options.

I originally intended to make the changes in the context of a PR for activeadmin-select2, but diverged quite far from the original feature set during development. Also activeadmin-select2 provides additional features (multiple selects, tag selects) which I do not need at the moment and which would have been extra work to integrate with the new functionality.

I've included a link to this repository in the acknowledgements section of the readme and incorporated your copyright information into the license file. I removed your personal data from the gemspec since ownership of the new gem will be held by us. Please let me know if there is anything else you'd like me to change.

Thanks for your work on activeadmin-select2.

Best regards
Tim