Add email tests to the verify EZID scripts

[jsjiang]

EZID uses the django.core.mail.send_mail() function and the EmailMessage class to send emails. Add tests to cover both.

The django.core.mail.send_mail() function is used in the following scripts:

• ezidapp/admin.py
• management/commands/proc-crossref.py
• management/commands/proc-download.py

They all use the send_mail() function in the same pattern:

django.core.mail.send_mail(
                        subject, message, django.conf.settings.SERVER_EMAIL, addresses
                    )

So a test that can cover the above send_mail function with the same parameters should be good enough.

The EmailMessage class is used in the impl/ui.py script to send Contact Us email to the EZID account. The ezid_ui_tests.py has a test for the Contact Us . Make sure the email notification goes through.

[jsjiang]

Modified the ezid_ui_tests.py script

• replaced the hard coded fake testing email " ezid.test@cdl.org" with input from the command parameter
• made the user email a required command parameter so the tester can enter and verify email notification
• this tests sending email using the EmailMessage class

[jsjiang]

Modified the verify_ezid_after_patching.py script:

• added an additional required command argument --notify_email for receiving download notification email
• made username and password required command arguments
• this test sending email using the django.core.mail.send_mail() function

[jsjiang]

Deployed with release v0.0.9