Convert existing int timestamp fields to datetimes

[zpchavez]

Convert existing int timestamp fields to datetimes

Acceptance Criteria

1. The following columns are auto-updated datetimes
   1. users.created is an auto-updated datetime.
   2. user_tokens.created is an auto-updated datetime.
   3. emails.created is an auto-updated datetime.
   4. emails.updated is an auto-updated datetime.
   5. Anything I may have missed
2. Task exists for updating the database

Tasks

• Write upgrade task to change data types (doing so non-destructively will require creating a temporary column, converting existing int timestamps over to it, dropping the original column, and then renaming the temp column to the original name).
• Change updatedTimestampColumn to updatedDatetimeColumn
• Change createdTimestampColumn to updatedDatetimeColumn

Additional Notes

• {{list additional notes here, remove if not applicable}}