Allow user-created choices for selects

[joeworkman]

Description

This is essentially a refactor of https://github.com/Choices-js/Choices/pull/525

I feel that this feature is important. I feel that the original was never merged in because of the amount of work it was to refactor it into Typescript.

Types of changes

• [ ] Chore (tooling change or documentation change)
• [ ] Refactor (non-breaking change which maintains existing functionality)
• [ ] Bug fix (non-breaking change which fixes an issue)
• [x] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• [x] My code follows the code style of this project.
• [x] I have added new tests for the bug I fixed/the new feature I added.
• [x] I have modified existing tests for the bug I fixed/the new feature I added.
• [x] My change requires a change to the documentation.
• [x] I have updated the documentation accordingly.

[rainbowRider5]

I'd love to see this feature finally merged. @jshjohnson, @mtriff any chances?

[land0r]

Hello, any news? It's been without an answer for a while, maybe you have some plans and dates @jshjohnson, @mtriff Thanks!