Timezone dropdown

@Tally devs: I found a really good read on this subject - https://www.nngroup.com/articles/time-zone-selectors/

+1 This feels like a crucial addition as there's no thorough way to simplify the extensive list of hundreds of timezones. UTC offset does not equate to a timezone, and trying to shorten the full list at all would leave out some areas effected by DST. This is closely tied to user experience, regarding both the end user and form creator. For end users (aka the ones who are filling out the completed form), some might be used to typing in the UTC offset, while others may be used to typing in their closest city name. The available options should account for most autocomplete cases to achieve the best user experience. For form creators (me and most likely whoever is reading this), such a list would take up a massive amount of space in the form's Edit page, and since datasets can differ, there would be no unified experience for what is effectively a self made input block. Lastly, I'd like to share my specific reason I sought out this feature request. I previously used a short text field and let the user type in anything, which worked fine for about a year. Now I'm running into scaling issues from not having a proper project management suite, so I'm looking into services like Airtable to better understand and manage the data. One of the things I'd like to do is sort the records by timezone, but the inconsistency and misspellings from my existing timezone text field creates an obstacle. I'm not sure yet what I'm going to do to fix the existing data, but I do want to make an effort to fix said issue for future records.