This deletes a big ol' chunk of code related to letters. It's not everything—there are still a few things that might be tied to sms/email—but it's the the heart of letters function. SMS and email function should be untouched by this.
Areas affected:
- Things obviously about letters
- PDF tasks, used for precompiling letters
- Virus scanning, used for those PDFs
- FTP, used to send letters to the printer
- Postage stuff
so they can be distinguished on the frontend.
Also, some related cleanup:
* don't show test api letters on the frontpage
* make sure the subject is returned from the API for letters
* make sure the letter's address is returned for letters