Summary:
Ref T920. Over time, mail has become much more complex and I think considering "mail", "sms", "postcards", "whatsapp", etc., to be mostly-the-same is now a more promising avenue than building separate stacks for each one.
Throw away all the standalone SMS code, including the Twilio config options. I have a separate diff that adds Twilio as a mail adapter and functions correctly, but it needs some more work to bring upstream.
This permanently destroys the `sms` table, which no real reachable code ever wrote to. I'll call this out in the changelog.
Test Plan:
- Grepped for `SMS` and `Twilio`.
- Ran storage upgrade.
Reviewers: amckinley
Reviewed By: amckinley
Subscribers: PHID-OPKG-gm6ozazyms6q6i22gyam
Maniphest Tasks: T920
Differential Revision: https://secure.phabricator.com/D19939