[Submissions] Repurpose/rewrite Submission "lifecycle" emails for X week after preassignment

As part of the automated expiration/rejection of submissions, we want to revamp the emails sent by the automated messaging system to reflect the new procedure.

This issue the collection, cleanup, and repurposing of those many automated and manual emails into a cohesive group.

• Find emails relating to submission updates, automatic and manual
• Preserve already present information on those emails
• Repurpose the views and templates of these emails into the new workflow

Email Scaffolding

• "We have not been able to find a suitable editor"
• Conditional logic for providing appraisals if they exist, at week 1 (#338 (closed))
• "However, there exist some assignment offers..." (#338 (closed))
• "Your submission is set to expire on ..." (#335 (closed))
  • "You may extend the expiration date by 1 month", only once (#335 (closed))
  • "You may contact edadmin for additional extension", if self-extension has occurred (#335 (closed))