Consume emails and forward to queue

More info with imap example https://codimd.web.cern.ch/PsY0aR0sRsaYDvqdeBBMNQ#Consumer

• Use Imap to consume emails in a loop (ie fetch 10 most recent)
• Make search criterion configurable (one container will consume critical other all (except critical if possible)
• Make destination queue configurable (one container will send to np.email-gateway other np.email-gateway-critical)
• After successfully moving to queue forward the email to a new folder eg processed for storage for a period of time TBD