Can we support a note to translators when submitting a job?

[stevejalim]

On the page where we select languages and a due date for a translation job it would be good to add a text input where we can attach a message to the translator about the work.

We'd need to decide where that would be surfaced on the Job - if there's nothing more fitting, perhaps we can add it to the Job's description, as long as there's a viable character limit for that field

[stevejalim]

Talking with someone on our L10N team, adding the note to the description field would work