Set up error email & template

[thashepherd]

From the project reqs:

If an error occurred, send an email to team@codefordayton.org so we can troubleshoot it. This is really important! Filling out the form via parsing the html is necessary but brittle. If they change the form in a way that breaks the submission, we'd like to know about it. :)

This is another task that might require a bit of design work and/or refactoring of existing code. We'll need to ensure that we're sending an error email in all cases when an error happens, which will require some manual testing. We'll need a way to provide that team@codefordayton.org email address as an alternative to MAILTRAP_TO_ADDRESS, and potentially a new jinja2 template.

It may be a good idea to either pick up #17 before tackling this issue, or work closely with whoever is solving that problem.