Make graphie produce the same hashes as before

Summary: Previously, because of how we set the values before posting
them, newlines were replaced with `\r\n`s. This emulates that behaviour
in the new interface.

Test plan:
 - Render templates 0, 8, and 17 in the old (3c49ac05) and new graphie-to-png
 - Ensure that they have identical hashes

Auditors: alpert, aria