Add ability to specify a tag that you want to create.
Help from Anthony Mangano:
https://github.com/wangteji/Sunsingnim/blob/e8f3151e1f0debc148602ed821780cd02fe5e47b/app/assets/javascripts/chosen_plus.js
Edit comments and spacing
Remember to save, not just .new a Tag
Add ability to delete tags that the current user has added
Add validations to enforce uniqueness of tags
Disable tag choices that are already added, and enable search