Create email based submissions

[anusharanganathan]

with bagit package containing

• [ ] Metadata files
• [ ] Data paper
• [ ] Supplementary files

[anusharanganathan]

The email only needs link to data paper page and no attachments. See https://dev.data2paper.org/rails/mailers/elsevier_mailer for a preview of the email sent as per spec

Added ability to send pre-formatted emails to the journals service email. Can use mailgun and a background job if needed in the future

Commit 7b3d361b083

Reference https://launchschool.com/blog/handling-emails-in-rails SendingEmailsinRailsApplications.pdf